I didn't play football, but I played lacrosse. I can tell you this:
1. You will train very hard, and coming in as a freshman you will be working twice as hard. You should plan on running 3+ miles a day and lifting weights 2x a day + practice sessions to even think about rising to a starting sophomore position.
2. Plan on eating breakfast lunch and dinner with your team. After all the 5am running drills, breakfast, class, mid day weights, class, lunch, class, practice, shower, dinner, its time for study hall until 8-9. Then you can play video games and dip a shit ton of Copenhagen straight cut until you eat the Tylenol pm and fall asleep.
3. Go ahead to GNC and stock up on protein (52 grams per scoop is best) and when your on spring and summer training camps get NOxplode its a BSN product.
4. After getting shitfaced and slaying chicks you shoulde eat at least two cans of tuna fish post bar trip. I mixed up bumble bee tuna with chalulah and ate it with doritos.
5. Gain 20-35 lbs of pure muscle and you might get some PT.
or you could skip it... actually study and take your classes simi seriously and do your home work. Party on the weekends, ski and work out an hour a day and be awesome at college.
I played college lacrosse for two years then did a NOLS in patagonia and decided on the latter.
eat some boomers and just pic a major that will apply to you. If you love art take graphic design or industrial design. If you love people and products get into marketing or sales, if you love to anilize things get into sociology or psych.
Bottom line is you have four years to fall in love with what you want to do with your life.
If you can take a year off and be a ski bum before you go to college and that way it will be in your system not embedded in your veins.
good luck with your decision either way.