I want to become fat and slim everyone blame me that you are so week no fair please help me

I had the same problem.
It is all about your diet. Try eating more carbohydrates and natural fats like peanuts.
For more info you can check Build Muscle, gain weight (http://www.freefitnesstrainer.net). It is a little page I created to help people.

You want to become fat and slim? You mean bulk up? Proper weight training and protein always gets it done.