Im 18 year's old and my weight is 136.3kg. My height is 178cm...what exercise should i do? i want to get nice body..haha

There is a pinned thread titled 'Bodybuilding Routine'. Read it.

sit ups

Reading will give you a nice body. Sooooo much to read about nutrition, bodybuilding, exercise~ Really, why don't people search this very basic information?

Anyway, what is a 'nice body' to you? Is it like Schwarzenegger? Jackman? Downey Jr? Maybe skinny fat? Or just plain skinny like Bale from 'The Machinist'? I have a friend who likes skinny guys with flat bums (I call them twigs).

'Nice body' as a goal is too vague, it is equivalent to having no real direction.

If you are asking how to shed pounds, the simplest thing and healthiest way to do that is figure out your calorie needs for the day, slash it by about 20% and exercise at least 30 minutes 4 days a week (I suggest 2 days weight training & 2 days cardio). It will be slow steady loss assuming you didn't have an eating disorder, yoyo dieted in the past or have medical issues.

holyshit. 130kg and you are 18? how the hell did u end up there? lol.

shadowz gave a good advice. my advice, just start to do something. anything. walk, jog, eat right, etc. by doing something u'll know where u need to adjust and progress from there.