Just give it a try. Try to talk to others, you don't need a lots of friends all you need is a true friends that will stick with you thru thick and thin. You don't need to act like all friendly and be friends with all of them just try to talk with those people who you'll think you had the same interest, just don't be shy for sure there's someone out there who'll want to be friends with you.
I can somewhat relate; I also can't adjust/ be comfortable with my new friends as well, but I think you just need some time. Maybe you are just comparing your new friends with your old friends, so you may feel like you are just being left behind, but I'd say just give it some time and genuinely look at your new friends and actually get to know them better without comparing your experiences with your old friends. It may be awkward and uncomfortable at first, but that's part of the process.
It's like a reset of a game; it's difficult to kill enemies with a basic weapon/skill (not knowing anything), but the more you get items and gear (geting to know your new friends), the closer you are at getting back to your old stats (familiarity and comfortability) before the reset
I am also trying to gain new friends in university, and it feels uncomfortable, but after a year of being here, I think I am slowly getting used to the people I talk to; I am also getting closer with people whom I didn't talk to last year. My point is, just go with the flow and your situation would eventually improve.
So im moving to a new school next year. All my friends are too. We obvs have a gc where we talk with each other. Lately its not that active anymore. Like we don't talk that often. Im mostly cool about it since I dont really have anything to talk about. I however noticed how theyre all having new gcs with their future classmates/schoolmates. (I also have one but I dont talk unless theres a topic i relate too). I can tell how much theyre enjoying it. Im happy for them as well. But i get sorta sad now that I see how happy they are with these new people. I know that its good that theyre getting along with others but it saddens me that they dont talk to me all that much anymore now that theyve got new people to talk to. I guess im also jealous since they have new friends and wouldnt have a hard time adjusting to their new school. I feel like im being left behind since im not making new friends or being close with anyone new.
I wish i were like them. As friendly as them.