My wife is pregnant from 6 to 7 week but she suffering from vomitting even she drinks water doesn't digest. she also not going potty since last 5 or 6?

Common: Nausea and vomiting is quite common early on during pregnancy. It is often worse in the morning. I would recommend small non-oily meals throughout the day. Banana, rice, toast are great options. Gatorade or similar products with electrolytes can also help replenish fluids/salts. Use Vitamin B6 twice daily and that can help as well. If symptoms persist, see Ob, who can prescribe more meds Dr M