I'm 19 years.I weigh 79kg.my height is 5.5feet.I have a lot of fat at thigh and hips.so what should I do 2 reduce s fst as posible...

One of my close friend lost over 8 Kg weight in 6 weeks, by strictly following a diet plan. I have seen him in the office everyday, eating fruits as food from his diet plan. You can search for diet plans to reduce weight. Plus some regular exercise will help a lot. At first it will be difficult to follow the plan, but once you stick to it for three days religiously, then you will definitely cross the 6 weeks or so period. You can do it, I bet.
I will not suggest tablets or liposuction.

Contrairy to popular believe building muscles have an higher fat metabolic property then cardio alone. I would recommend you start building some muscles up. Do this by compound excercises. The beauty of this is you can keep your dieet the same just replace some of your carbs with protein.

The best excersise for that would be cycling if you have a bike-or even better,running,if you live in a built-up or city like area its best to get a treadmill.Running is probably the best form of excersize because it will burn the fat at the top of your thighs and hips-
Hope it helped :)x