My stomach sides and back fat is hard to get rid of what should I do?

You can't lose fat . Only on specific spots. But generalized weight loss is often helpful. Eat healthfully ; be physically active. Aim for 7.5 to 8 hrs of sleep / night. Hydrate w at least 64 oz of water / day. Calories burned must > calories consumed. Do both cardio ; weight training. You can mix ; match different kinds of physical exercise.
Eat less & exercise. It is impossible to dictate from where you loss fat. It would appear that we all have a predisposition to carry our excess calories stores (fat) in specific spots. It appears that you store it in your stomach and back regions. All you can do is steadily burn slightly more calories than you take in, and you will loss weight and excess fat. However, it will likely leave your stomach & back last.