My bio dad left when he first found out that my mom was pregnant and they weren't married or anything he gave up all rights to me and when I was 5 is when I found out about all this and now I am 13 turning 14 and we went to the movies that day and my mom pointed him out to me and I saw him chasing after his kids to his wife and I really got over that but I want to know if there is some way to get him back in my life because even though he left my mom when he found out, he is still my bio dad and I want to meet him. Is there anyway I could find him?
And is there anyway he could get any rights of me (if wanted to)?

But alls I want to do is find him and meet him. Is there any sites I could go to for that?

Because you are a minor you would have to have your mothers permission. She would have to be the one to contact him and everything. Once you turn 18 you can try to contact him but he can refuse.