My upper body has a good shape but my lower body is fat (stomach, hips, thighs). how to lose fat in those areas?

Many options: Weight loss, liposuction, coolsculpting, and excisional surgery such as abdominoplasty. The first option is always a good place to start since it doesn't cost anything and the risks are almost non existent. Then go to see a plastics surgeon to see which of the other options would be best for you.

Spot fat loss does : Not occur naturally. By losing weight in general a certain amt will probably be ab, hip, thigh fat. However, we don't get to chose what area of the body the fat is lost from. 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.