Of course it’s not too late, it only appears harder because in school we spent a lot of time during the week with many people the same age. But only a fraction of that time is needed, all it takes is being around people and talking to people.

Many on lemmy rightly complain of the lack of “third spaces” nowadays in many of the richer countries (you said college I’m guessing US or UK?), so for example in many places it’d be a bit weird to just go to the pub alone. But you can also just go alone and do and enjoy whatever you want, it just takes a bit more confidence, the embarassment of it usually wears off with age for most.

What’s probably easier is joining some semi-regular activity where you get to chat. So pub quiz night, language exchange, chess club, hiking group, etc… are more likely to aid you in this compared to loud night clubs, the gym, or whatever, it’s all subjective it’s still important to do the stuff you enjoy, regardless of socializing.