Like the person above me it would be New Adult and it does sound like you haven't gone to college yet, but seeing as I'm currently in college I can give you some of my findings. One there are people watching over you. At my school we have security which is very strict and rules that we must follow - such as never jumping into the school fountains because its a $500 fine - so yes there is an amount of freedom that one has, but its not absolute.
It is now up to you aka your character to decide whether you want to go to class, but miss too many and you might fail or in my case miss 4 and you get kicked from the class. We actually have attendance so that hasn't changed and then there is all the homework that your character will have to do.
Frats & Sororities: While they are not as dumb as many movies like to make them out to be they are pretty stereotypical in my opinion. The guys are all obnoxious - and I have frat and sorority friends who aren't - but get them in a group with alcohol and its sad how fast their appeal goes down hill. I know my freshman year two sororities had a major rivalry going on to the point where I knew a girl who told me she was rushing Zeta and her friend KD and so her friend told her they could no longer talk. Now that has changed, but that is always something interesting to throw in.
Parties: When you aren't 21 you go to frat and house parties which are generally loud, dark, and packed. People smoke outside, drink inside, and if you aren't 21 the guys who sit out front will mark your hand so that you can't drink. Usually by 1am security breaks up a party which means you've got to move somewhere else. If you wanna drink then your character would have to pre-game in their room which requires befriending someone older with either a fake ID or an actual ID who can supply you.
Then of course you just have to deal with making friends, boyfriends, etc...
There are many crazy experiences to be had in college and they are different for every person.
Hope this helped!