I Can Only Become Stronger with Self-Discipline

The Male Protagonist Has Trained Hard Since Childhood to Become Invincible.

I want to read a book similar to "Armor: As a Human, I Appear at Full Level".

A Book That Asks the Protagonist to Exercise Self-Discipline and Gain Knowledge

A Book to Improve Self-Discipline, Study, and Improve Comprehensive Knowledge

I want to read a book similar to "Understanding Social Reality and Being a Human Being".