Usually when you get a job, I would pick something you are kind of interested in. Also you have to understand that minimum wage is $7.25 a hour and that's not much. A fast food place is typicality the easiest place to get a job. My first job was Subway and it wasn't a good experience to me. The owners and everyone treated me good but working at fast food isn't for me and for $7.25 a hour, na I'm good.
Usually when you get a job first you have to ask for a application and wait until they give you a call or ask you to come back a certain day. If they call you and set up a meeting then you better show up on time if not earlier than what is expected. Also you should wear something casual and not your pajamas but make sure you don't over dress. Also you should make sure your using manners like Yes mam or Yes Sir. All that matters is where you are trying to work at. If you trying to work at a clothes store or shoe place, then you might want to dress pretty nice to show you have style. If you trying to apply at a fast food place then you could just wear some cargos with a shirt or something.
Having a job for me helped me learn how to manage my money and time. Having a job is also very time consuming and that's one thing I hated. Also if you get a job they might not give you the days you always want off, and that's another problem I didn't like. A job is good for some people though. It would allow them to get away and do there own thing and also have there own income. The reason why I quit was that I had rather be at home with my family rather than working like a slave for like $100 a week.