Are there any exercises i can do to increase my breast size?

No: There are no exercises or creams that can increase or augment your natural breasts. The only ways are fat transfer (fat grafting) or implant placement. Bras are a non surgical way to make your breasts appear larger. See a board certified plastic surgeon for details.

Exercises: Will help tone and improve your pectoral muscles, but don't do anything to the breast itself. Only surgery can do that.

Increase muscle only: Exercises will only increase the size of the pectoralis muscle which will negligibly increase the size of your breasts. The breast is composed of fatty tissue and exercise may actually decrease body fat and breast size. Non surgical breast augmentation options are discussed elsewhere here: medications, external expanders, garments, herbs, etc. But usually reliably accomplished with implants/fat.