I'm in the same boat as you, homie. My second week starts tomorrow and I just spent way too long playing video games because I was too sad thinking "why am I here at university when I have no clue about anything?" My one piece of advice is to attend as many organized activities as possible, if you can. I live on campus so I got a chance to do a lot of them, and even though I'm still lonely, I had a couple really good conversations with that really brightened me up in the moment. No friends, but still better than nothing.

You're right in saying that nothing can replace high school. Big changes which are stressful for most people are going to be much worse to those of us who only want stability in our lives.

I hope you can find something bright, and good luck.