I have a polyp sized 5mm and another two sized 3mm in my gallbladder, so what shall i do and eat so that its size doesnot increases & doesnot affect?

No effect: Diet will not affect your polyps.

Biliary diseases: Gallbladder polyps can remain without symptoms, are often benign, but cause concern. A low fat, controlled carbohydrate diet will benefit by minimizing stimulation of the gallbladder. Occasionally symptoms of pain, nausea and bloating persist to the point your doc refers you to a surgeon. Be well.