Hi Vikas, I live in East Delhi and my father was having treatment at RGCI. You have to quit smoking and drinking completely as your doctor is right. Your doctor has only prescribed Anti-oxidants for now.
The biopsy says that the white patches are not malignant but if the irritation persists, there is a possibility that they may turn malignant.
At this point of time, you are standing on the edge. Cancer is a terrible disease so quit smoking and drinking when you still have time.