I started working at Mcdonalds about a month ago and then there's this manager... the weird one I remember I hated him so much cause his comments irritated me.. and today when both of us were on break he was like did you have a PA day on Friday and I was like no my stupid gay school doesn't have that and he was like what school and I told him my school and that it was a very gay school and he was like I graduated there and I was like no wonder and he stared at me and I was like Jaay Kay and today when I was looking for him on FB I saw him kissing one of MCD cowerker and the picture was taken a year ago and I don't know I think I like him... what should I do?? And I'm turning 15 and I think he is like 19-24

Part of the dynamic of learning how to deal with your new feelings for people is to be able to keep your brain fully engaged in the process. Do not convince yourself that feelings are the most important thing of all and nothing else matters.

It all matters.

In your situation you have multiple strikes against this being a good idea to pursue in the slightest.

1) You're a minor and he is not
2) He's your superior in the workplace
3) You have evidence he "dates" in the workplace (meaning his own judgment is in question)

Just pat those random thoughts of "maybe I like him, what should I do?" on the head and send them on their way. Don't let them take root under your feet.