Among the works of Chinese studies, Disciples Rules is the first choice for reading and learning, and it is an introduction to Chinese studies, and the basic principles of Chinese studies are all in it. It's much easier to see other works after reading Disciple's Rules. Then, read the Four Books and Five Classics, Tao Te Ching, Zhuangzi, I Ching and so on.
The most important way to improve language use ability is to write more and speak more. Writing more and speaking more, practice makes perfect, and language proficiency will naturally improve.