I want to lose belly fat. where do i start.

Lose weight: Unless you have the abdominal fat removed surgically, it is not feasible to target fat loss to a particular area. You need to reduce your intake of food and exercise more.

Spot fat loss does: not occur naturally. By losing weight in general some may be abdominal fat. But, we don't get to choose what area of body fat is lost from. Eat healthy & be physically active. Calories burned must > those consumed. Tighten ab's: crunches, reverse crunches, exercise ball crunches, pelvic thrusts, lying leg raises, side bridge & “bicycling” exercise on back. Do regular aerobic exercise.