"Illiteracy" refers to people who have not received basic education and do not know how to read and write. "Evil" means that a person has evil behaviors and thoughts. Going to school means receiving a school education.
This sentence expresses the importance of education. Good education can cultivate healthy personality and correct values, and help people to better understand the world and understand true beauty and happiness. On the contrary, lack of education or receiving the wrong education can easily lead to people's wrong ideas and behaviors, and even lead to bad consequences.