I'm 21, how can I enjoy this age without much friends?

I feel like I'm missing out with my 21 year old life. First of all I didn't enjoy my high school years. I didn't have any friends. I was really quiet with low-self esteem. I've actually became more sociable after high school.. I only made one friend in high school and she's still my friend until now. I only have 2 close friends. One is my cousin and she doesn't even really count. My actual friend doesn't even enjoy partying like going to clubs or raves. The only "fun" thing we do is go to happy hour and buy drinks. Other than that we don't do much. My cousin, she has a baby so it's hard to go out with her since she has her baby as a responsibility. I just wish I had a group of friends who actually like going out but it just sucks how my only friend doesn't enjoy that. It's Halloween and I don't even have anything to do. I didn't go to any parties because I have no friends. It really sucks. I feel like my social life really sucks. I go to a community college so maybe that's why it's hard to get close friends. I also don't have a job so that might be another reason why. How can I change this? Do you think I will be able to meet new people when I transfer to a university once I finish my community college? Or even getting a part time job? I'm really not enjoying my 20's right now...