There are always people in the dormitory who want to fight against you and find fault with you. What should I do? How to get along with such people?

According to what you said, this boy is really picky, hypocritical and untrue.

When you don't live in, it's not easy to find too many problems with your classmates because you don't live together. Once living together, people's disguise will not last so long, they will find some problems that are not pleasing to the eye more or less, and of course they will meet friends who get along well, especially boys.

There is no need to waste your good time for one person and think about other things. Leave him alone. Let him say what he wants. The best revenge for the enemy is not caring. Ignore him.