At 19 don't try and figure out what you want in life. Just enjoy it. While your enjoying it think a little about it. Work at different places. Get a job. Doesn't matter if its fast food, restaurant server, or even a landscaper. Get a job. And do good at it. Don't just go the bare minimum. Go beyond. Make it to a manager position. Save money and do your job. That way you can enjoy being 19 and still be putting money away.
By the time you've got some saved up, credit right, and your a shift or store manager, you will have found out what you wanted to do as a career. And no it won't be fast food. Lol.