Don't sweat the small stuff - basic is what a person makes it. Keep a low profile, off the DI's radar and you'll be fine. If, however, they discover you or determine you to be in the special needs category - work yourself out of it.

When enlisting, choose an MOS carefully - do not be sucked into being a grunt. Unless, of course you truly enjoy being shot at. It ain't all that glamorous.

Basic is something like 18 weeks now. Was only 8 or 10 when I went through - many (many, many) moons ago. By the time you complete it you will be a fully qualified rifleman - the additional training for infantry is in cross weaponry, tactical, etc, etc, and additional P.T.
Jump school was 3 weeks when I was in, heard it is a bit longer now. But, all it was in my day was training one to jump out of a plane - period. ["The first week we will seperate the men from the boys. The second week we will seperate the men from the idiot. And, the third week the idiots will jump.]Once assigned to an Airborne unit one went through additional a much more elaborate training process - extensive. That much hasn't changed, but they are teaching the rope trick out of choppers now (which was an OJT thing for many - in 'nam).

So, pick an MOS that will be helpful in civy life - even if you intend to go to college afterwards. And don't sweat the small stuff. Also, keep you ass down, your head lower - and don't let those buttons get in your way of the ground.