Dix finished the tree climbing exercise the next day. He knew he had to practice more and consolidate his chakra control even more, but for now that was good enough. Naruto finished this training in the 'Land of the Waves' story arc, when he was around 12 years old, while Dix at this point of time has not long passed his 4th birthday. This made Dix feel really good, he could see the fruits of his work and his great progress. The next step was completing the water surface walking training which would help him practice his chakra control out of his body. While he wanted to start right away, he realized he doesn't really use chakra that way so he put it on hold for a time.
The most important thing he had to improve on now was his body. He was already on his way but this was a time consuming process, so he just had to be patient and build up his physical strength over time. He noticed his extensive training, while it hardens his muscles and builds up his stamina, it also help his muscles to take in and use chakra more efficiently, and refined his already existing chakra.
There was one crucial thing he lacked the most and was heavily burdened by. He had no one to teach him. He almost reached to the point he wanted to by raw stats, now he had to learn techniques and jutsus. But... he was still 4 years old. Most kids only play and run around not caring about anything in the world while their parents provide for them. There was no one out there to teach a stupid little kids that had a hard time not shitting their pants. Only if he had some sort of relatives that are ninjas or something... Usually clans, like the Uchihas start training their kids at a really young age, around when Dix was then, but they would only get to learn basic chakra control and hand-to-hand combat at best. Event the militaristic and proud Hyuga clan starts actually training their young ones to ninja combat at the age of 6-7. Dix had no way to find a suitable teacher when he was 4.
The second best option would be finding data trough public libraries. The most basic techniques and chakra related knowledge are usually available for the public, as the society in this world is advanced enough for public libraries to exist, and such basic knowledge had no actual value so they were easily accessible. The one problem Dix had was that he's still just... 4 years old. Once again. Usually kids can't really read or write at this age.
But actually this wasn't much of an issue, because Dix already foreseen this problem. In the orphanage there were classes for basic knowledge for kids who would otherwise land on the street if left as they were. Getting them basic education helped everyone, so these lessons were readily accessible for anyone and Dix was the last one they would've barred away from... anything. As long as he was quiet and would keep to himself in the back of the classroom, nobody even looked at him. They thought he is just quirky and wants to be around, so they let him stay, while in reality there was a time when Dix held back a bit on chakra cultivation and used most of his time to attend most of the classes possible, even those for older kids. Thus with his dedication and boosted brain capacity he was able to finish the basic education in about one and a half year, which usually took around 3-4 for normal children. All the while he kept on practicing and training his body.
So when he faced the problem of his lacking knowledge, he was able to rely on the libraries. Even though everyone looked at the kid walking into the library with nasty expressions, nobody got in his way just as before. Inside he found scrolls explaining the nature of chakra, which he already knew about. He found other interesting data, such as history and arts, theories and dissertations on different techniques. He even found some books writing about ideologies and culture. But that didn't really interest him, even though he decided to read as much as possible in the future. After a bit of search he found his target, there was a section with many bookshelves packed to the brim with different basic and low level techniques and jutsus.
He started rummaging trough them with high fervor and found better and better skills every minute. He took out a few and tried to memorize them. His boosted brain was able to soak up most of the required knowledge and theoretical background he needed to study a specific jutsu. He found most of the basic ones they are taught in the Academy, like body transformation, clone technique and replacement jutsu. He even found a few scrolls about how to properly throw kunais and shurikens, how to properly handle specific hand-to-hand combat scenarios etc. These were all the basics and Dix felt like these are useless.
If you asked a random bystander they would say ninjas are all about shady missions and stealthy information gathering behind enemy lines. Even the manga and anime wanted to enforce this idea in the beginning of the series, while actually this 'fact' couldn't be further from the truth. In Dix's first life in the Warring States Period Japan, where the concept of ninjas come from, this was a reality. Ninjas were masters of infiltration and subterfuge, and were specialists designed to handle very specific missions like assassination, espionage and sabotage. In the world of Naruto this is a bit different.
In this world ninjas are often used as the main army of the villages and their respective feudal lords. There are obviously samurais and other footsoldiers, but these are simply nowhere as good as a well trained chuunin level ninja. Training samurais take way more time, around 8 years, and are usually on equal terms with ninjas, or sometimes even lower, while training a genin ninja usually takes around 3 years and they are usually able to handle themselves quite well. This means ninjas are used everywhere, when it came to undercover missions, or when it came to nuking a random village somewhere in the countryside.
Ninjas have an extremely wide range of abilities and possibilities. These can range from simply changing their appearance all the way to sweeping off a village with the water they can generate from their guts. These people had incredible powers at their fingertips and they never shied away from using them. Thus Dix had an impression, that ninjas are more like demigods or natural disasters walking among mortals instead of subtle specialists. These previously mentioned techniques are really great for the latter, but Dix knew he won't be doing any of those. He practically had a recharging nuke stored in his belly, so he was pretty sure he won't be sent on undercover missions.
But nonetheless Dix decided to learn everything. The foundations are the most important. He could build up his knowledge and strength step-by-step. Dix didn't want to slip up by being arrogant and not learning the basics because he feels like these skills are 'useless'. He wanted to gather all the knowledge available to guarantee his success. Thus, he memorized all of them. He wanted to bear less knowledge in his brain rather than more, because he didn't actually master these skills yet. He had to go back and master them trough actual practice before moving on to others.
He thought he had enough, but some divine inspiration made him continue on. He wanted to see if there is one specific jutsu he had in mind on one of the shelves. The one and only true ultimate jutsu that stomps every other. He looked for it and looked some more. He was about to give up when he caught a glimpse of the title of The One. This might not be the strongest, or this might not be the flashiest, but this one jutsu is one of the greatest cheats for someone like Dix. This of course the second signature skill of Naruto, that he always relies on.
This of course is nothing else than the famous Shadow Clone Technique (KAGE BUNSHIN NO JUTSU! :< Also it seems like some people are dissatisfied by the seemingly random appearance of this jutsu book. Let me explain things a bit. This is not a forbidden jutsu, that one is the Multiple Shadow Clone Technique, which forces the user to divide his chakra reserves many many times, which is potentially lethal for most ninjas. The simple Shadow Clone Technique is technically the same, but does not force the user to summon many clones, thus it is perfectly safe to use, because even if the user overexerts themselves, they can't summon so many clones at once to kill themselves right away, it mostly only gets to loss of consciousness due to exhaustion. Now, even though Shadow Clone Technique is a B rank jutsu, this tier system does not represent the rarity, more like a combination of how hard it is to use it, its usage requirements and its strength. This technique is the most common high-rank technique, every jonin level ninja can use it, and many chuunin too, only being high rank due to its extreme chakra requirements and difficulty to master, other than that it is fairly plain and has close to 0 military value due to it being so common. Considering this it is not so extreme to find such a technique in a library where common techniques are recorded. It should be rare in a place like this for sure, but as it is said later, he also got some "extra luck" here.).
Once created, shadow clones can serve a number of purposes. They can be used as decoys, either by keeping opponents preoccupied or, because they can't be told apart, concealing the original's identity. If enough shadow clones are created, they can simply overwhelm an opponent, pinning them down or attacking from multiple directions. Shadow clones can also be used simply to assist the user, joining the user for tactics they can't do alone or being sent to carry out tasks while the user is busy. If, in the latter case, shadow clones encounter unforeseen obstacles, they will behave just as the user would in the same circumstances. Because they have their own chakra, shadow clones can perform other jutsu, including making more shadow clones.
Shadow clones usually disperse once they are struck hard enough, but they have been shown capable of enduring injuries for a time. When a clone's task is completed, it can disperse itself or be dispersed by its user. Once dispersed, the clone's experiences and remaining chakra are transferred back to the user. The shared experiences make shadow clones useful for intelligence gathering: a shadow clone can be sent into hostile territory, gather information without endangering the user, and disperse when finished, thus transferring what they've learned. Alternatively, shadow clones can recon an area, dispersing when they've found what they're looking for in order to let the user know the target's location.
But there is something even better. The shared experience gathering works with training and studying too. This means someone who has such monstrous amounts of chakra, like Naruto had in the anime, or in this case, Dix, would be able to shorten the training time of different practices drastically and even learn and study other stuff all at once. This is a game changer and it would skyrocket Dix's improvement. If it was scary how he had progressed so far, then this is where the real fun begins.