I am not fat but I suffer from fats inside my belly and it would never go away, I have tried diets, am working out on regular basis and my body shape is not bad but when it comes to my belly its killing me... I need to find some serious ways/methods to have six pack abs or at least without having fats and thanks. :confused:

Sit ups won't remove your belly fat but build your abdominal muscles while reducing your overall body fat by burning calories.
The only real way to remove the fat from your belly is cardio exercise.
The best way that I've found is doing sprint intervals with abdominal exercises, such as sit ups.
When you run, try to intensify your workout by starting with a jog then adding 1 minute bursts of sprints (run as FAST as you can) then return to a light jog, and repeat. I like to do this as for about 20 minutes before a lifting weights and then for another 20 after lifting weights.

Of course it could be other factors leading to the consistency of your belly fat.

As well as your exercise, keep to this guideline of caloric consumption.

This is how your caloric consumption should be broken down.
-40-60% of calories should come from carbohydrates (simple and complex sugars, including glucose, sucrose and fibers.)
-20-30% of calories from proteins (you need complete proteins for your body's well being. Meats, fish, soy, and quinoa provide complete proteins)
-20-30% of calories from fat (limit unsaturated fats and aim to completely eliminate trans fats. Saturated fats are the way to go.)

Feel free to ask me to elaborate on any of the nutrition facts and exercise methods.