rb.
What do you think I should do? I'm lost
Ok, that's a start. As an rb, in terms of fitness, your primary concerns are most likely:
1. Speed & agility (to avoid tackles): work on sprints (20 yard, 40 yard, 100m, 200m), plyometrics, and agility drills. Extra bodyweight here is typically counterproductive.
2. Strength & power (to break/absorb tackles): work on squats, deadlifts, bench press, overhead press, cleans and snatches. Extra bodyweight here is typically *very* helpful.
3. Stamina/endurance (to not get gassed immediately): work on your "metcon" by doing interval training, timed workouts, gassers, burpees, rowing, stadiums, etc. Extra bodyweight here is typically counterproductive.
Look at the list above. Most likely, some of those items are strengths for you, while others are weakness. Most 16 year olds, for example, are fairly small compared to the upperclassmen, so their biggest weakness is #2. This means bulking up while building their gym numbers is the priority. On the other hand, some 16 year olds are too damn fat and need to cut down to get better at #1 and #2. Figure out what you need to do.
BTW, what are you currently doing for training now? What does your diet look like?