Can you answer me?

To make a good relationship with classmates you just need to pass a smile first of all. It will make them know that you are approachable. Ask them about their life, where they come from, and about their studies. Keep your behaviour simple and be transparent. Do not be fake, but you yourself be aware of fake people.

Just be yourself and be nice

Be nice to everyone. Have a smile on your face, keep interacting, help those in need.

Be prepared to make the first move. Smile. Help people out. Make yourself approachable. But above all else, don't waste your time on people that you don't like. It sounds harsh, but why make yourself be friends with someone that isn't really worth your time? Be ready to cut off toxic people, but give everyone a chance. In short, be nice :)