After confirming Haruku's thoughts about why he wants to become a shinobi, Yagami begins to teach him
"Haruku, in order to become a shinobi, you must first understand what makes a shinobi different from ordinary people."
"Father, is not it simple; shinobi have chakra and they use it to perform various techniques, which makes them different from others who do not have chakra?"
Haruku confidently replies, believing it is the most basic question.
"You are right, Haru, the use of chakra makes them different from others, as even a simple transformation technique requires the use of chakra."
"But you are also wrong, because it is not that only the person with the chakra can become a shinobi; the truth is that everyone has chakra in them: it is just the use of that chakra that makes them different from the others."
Yagami corrects Haruku, which puzzles him.
"Father, if everyone is born with chakra, why cannot everyone become a shinobi?"
I know that every year, many children apply for the ninja academy, but many fail because they lack the talent to use the chakra."
Haruku becomes confused ,but he patiently asks Yagami about his doubts.
"Well, let me start from the beginning."
"It is assumed that thousands of years ago, there was no presence of chakra. It was actually the sage of six paths who spread chakra to everyone intending to create peace using chakra to connect people's spiritual energy so that they can better understand each other without even speaking.
His motive was to spread peace and end the hatred between peoples to stop the wars and conflicts.
However, the people did not use the chakra in the way Sage hoped; instead of connecting spiritually, they weaponized it and continued to cause even greater war.
Since the Sage of Six Paths spread the chakra, it has evolved into a type of life energy that all individuals produce to some degree. It represents life; if you run out of it, you die.
"Father, if the chakra represents life, how do you use it?" Only now did Haruku realize that he did not have a clear understanding of the chakra..
"No, we do not use it; the chakra a person is born with is known as the inner chakra, and the chakra we use is a combination of spiritual energy, physical energy, and the inner chakra."
"A shinobi kneaded his physical energy, spiritual energy with their inner chakra to amplify it after which we can use it to perform various techniques"
"Okay, Dad, I understand that the chakra we use is a combination of spiritual, physical energy, and inner chakra, but how can a shinobi use different elements? What is the nature of the chakra?"
Yagami was very pleased to clear his son's doubts, and hearing his logical doubts made him proud of his son.
"Haru, do you know that our body is made up of five elements namely fire, wind, water, lightning, and earth, and that is why when we combine physical energy with spiritual energy and inner chakra it gives elemental form to the refined chakra, and when we knead the chakra for using ninjutsu we knead it in different ratios with the help of hand signs to produce an elementary jutsu, and generally peoples are born with dominant elements which make them easier to master that element."
As Yagami continues to teach Haru, he begins to explain more in detail.
"oh! so that's why there are 5 types of elemental jujutsu"
Haruku thought that after refining his chakra, he will soon be able to master a lot of strong jutsu, but only now he was learning that's's even using basic elemental jutsu will require a lot of hard work.
"Well, there are not only five natures of chakra, but also two more known as Yin and Yang. Yin is the nature of spiritual energy, while Yang represents physical energy, and mastering these two elements can increase the power of your jutsu.
Mostly the use of yin nature is done in genjutsu
And yang nature is mainly used by medical ninjas."
"Then, father, how can a shinobi master all these chakra natures?" Haruku again asks his father
"Mastering nature is not easy and is more difficult, but I have already mastered three elemental natures."
"And the third hokage has mastered all of the chakra nature, which is why he is feared on the battlefield."
"father ,if mastering the nature of chakra makes them that stronger than what is difference between the potential of a civilian shinobi and a shinobi who belongs to a clan"
"Hmm, it is because of the bloodline of the clan shinobis; as they have generation after generation of ninjas in their clan, they have better developed chakra pathways and they may even have some special traits that make them more powerful than civilian shinobi and they may even develop some special techniques which they can pass down to their later generation, and that is why a civilian shinobi will be generally weaker than the clan shinobi.
There are also more powerful clans, such as the Uchiha and Hyuga, who have their own doujutsu techniques which sloley belongs to.
So, because they did not have anyone to guide them, civilian shinobi have lower potential than clan shinobi.