What are some tips you can give me for weightlifting and football?

Depends On...: Strength training for football depends on your position played, age, development, and where you are now. Off season, you want to increase strength, size, and power. I'd include bench, squat, clean/jerk, snatch, and medicine ball work. Work on core strength. For explosive ability and speed, include plyometrics and ballistics.

Strength training.: You definitely need training for muscle strength - heavy weights, slow controlled movements. Core training will help with rapid movements, such as launching off the line of scrimmage. Sprints and jogging for speed and endurance, respectively.