I am 22 years single girl I gaind weight due to diane pills how can I lose my weight and stomach fat?

There's no such . Thing as natural spot fat loss. You need to lose weight in general ; a certain % will be abdominal fat. Eat healthfully ; be physically active. Calories burned must > calories consumed. To tighten ab's do crunches, reverse crunches, exercise ball crunches, pelvic thrusts, lying leg raises, side bridge ; “bicycling” exercise on your back. Engage in regular aerobic exercise.