I have a good height(5'9) but I have a tummy and my hips and bums and thighs have a lot of fat. Even if I play or do cardio excercises the sweat comes from my back and not tummy. What should I do to decrease my tummy, bums, thighs , hips and chest? If sweat is not the form of fat then how to lose the mentioned things?? please answer??

The idea that sweat gets rid of your fat is completely off...

So if you sweat from your underarms, you're losing underarm fat?

To lose fat, there are two important aspects: diet + cardio.

Many people always complain about how much they exercise but they're not losing weight... and that's because they forgot the other aspect: dieting.

Got to watch what you eat. It makes a HUGE impact.

I'm losing weight because of exercise, I'm worried about flabby tummy and flabby underarms, what type of exercises will be good to firm them up?

The tummy/arms will come off naturally the more you exercise. You can help tone the tummy and underarms by doing situps and crunches, and by doing minor weight lifting.