depends on what you're good at. At 5'8, you should probably try running back because most little men have a better advantage of getting around their opponents that are bigger than them. Think about it.
RunningBack
fullback?
Anyone you choose! - Most coaches would have you on the line
corner back
Cheerleader.
Bench Warmer
Defensive tackle
anything but defensive linemen
if yoiu are fast corner, saftey, running back maybe fullback haha dont matter as long as you lace people
Waterboy.
high school?.. sounds like you should try tight end.
Wide reciever, safety or cornerback