In my experience at a large state university back in 1982-83 when I was nineteen, I didn't really meet people in classes.
It was the dorm where I met people, esp something casual like walking to a convenience store with dorm mates (people on your floor, maybe not your roommate, but maybe people across the hall) or walking down to the gameroom.
But also, the dorm had some bullying, both criticism and at times physical intimidation, almost as if it was a recourse to junior high. A group of guys throw together establishing a hierarchy, as if we were chimpanzees sorting out who the alpha, beta, etc males are. Damn unfortunate, damn unnecessary.
I recommend taking some individual boxing lessons and learning some skills, for a baseline of confidence. The approach of tight, defensive boxing to a draw. And of course, yes, walk away from a fight if one reasonably can. If you "win" the fight, don't brag. Sometimes you'll lose. Only works against person own size. Please don't take a bunch of blows to the head during training, stuff about post-concussion syndrome and even repeating lesser trauma, largely true and boxing headgear doesn't really protect. Useful to have if necessary, hoping not to use. And I wish the world wasn't this way, but sometimes it is.