Will my skin be saggy if i dont eat?!

You need some serious mental help.
Yes your skin will get saggy and will look terrible, you'll start loosing your hair. Your nails will break and split, you'll feel weak and won't be able to concentrate. Your organs will start to fail. You'll probably faint a lot, so you could hit your head and die or you could give yourself a really big scar on your face and knock out some teeth.

If you really want to loose weight, start exercising. If you can't join a gym, try dancing to music, lift water jugs, get some exercise bands and use them, try yoga, walk and jog, ride a bike.

Remember, you'll lose weight if you have a deficit of 3500 calories so you need to find your resting metabolism calorie burn and add the calories burned from any exercise. Calories burned needs to be more than the calories in the food you eat to lose weight. So start tracking your calories. There are tons of sites online that can do that (for example MyFitnessPal). Never eat fewer than 1200 calories a day, otherwise you'll kill your metabolism and screw up your system and then you'll always be overweight.

http://www.prevention.com/health/fitness

You won't lose weight if you stop eating.

Actually, ok. You will. But you won't lose fat. You'll lose muscle. So yes. You'll be saggy and stretchy, and look sick. But still fatty.

And then when you start eating again (which you will... because you'll be starving) you'll actually get fatter, because a metabolism is made up of muscle. If you let your body eat up it's muscle... then what do you expect to burn fat with?

Being 30% body fat is still 30% body fat whether you're 140 pounds without muscle or 170 pounds with muscle. Wouldn't it be better to eat well, have energy, exercise, and enjoy life?