It's no use worrying. You should take the initiative to get along with them and treat them as friends. They will naturally treat you as a friend. You are worried that they will bully you, which means that you treat them with a hostile attitude first. How can they be nice to you?

I used to study in a different place, and the situation was similar to yours. There are many mixed classes, but they never have a problem with me. What you have to do is to be generous, frank, tolerant, aboveboard and get along with everyone in good faith when dealing with them.

If some of them take the initiative to find fault with you, don't be afraid, unless they don't respect your personality, you will fight back. Be honest, endure if you can, try if you can't, and fight if you can't win, and they will fear you.