As cultivating spirit grass requires one year before harvesting, Lin Yi planned to first advance his cultivation level to the complete ninth stage of Qi refining. After that, he would start preparing for foundation establishment. Upon reaching the foundation establishment stage, he would have enough confidence to start alchemy.
The transition from Qi refining to the Foundation Establishment stage is the first major challenge that cultivators face. The difficulty of breaking through to the middle and later stages of Qi refinement is not even one percent of that of foundation establishment.
This is a critical step to officially enter the Immortal Way. Once crossed, your lifespan doubles, and you become a true cultivator who can fly with swords and roam the heavens.