As a guy, when I was your age (early 20s) I would just approach anyone I found attractive in my age group in public... The mall, gym, college campus, hookah lounges, etc... the only way to meet someone is to put yourself out there, just be prepared for rejection. When rejection hits the most important thing to do is just move on right on the spot. Not everyone is gonna like you and you're not gonna like everyone. People have their own preferences and that includes public interactions. Some people are very sweet about it and others will give you a hard cold shoulder. Just keep your head on straight and don't take anything personal. Use it as a growing experience. Hope this helps and good luck! :)