i don't feel that different at 22 than i did at 18, honestly the biggest difference is that since i started living alone i get excited about discount sales for kitchen utensils and toiletries LMAO
can't give ya advice considering i'm not american and thus won't be getting the same experience as you but... honestly, attend all (or most) of your classes and enjoy your first year while you can. if it's anything like here, it'll probably be the easiest one and you can still party around or whatever it is you do for fun, even if ya gotta drag your half-dead body to class the next morning.
It doesn't matter what age you are. I am 23 in a few days, my friend is 30+ and we are both at University together with part time jobs. Same stage in life just one has been here longer. Nothing changes really just you to make your own food sometimes