Skin and hair. Please help me.

My hair- too frizzy, dry and lame hair, excessive hair fall. Stubborn dandruff. Itchy scalp, grey hair front Crown area. Slow hair growth. Skin- hyperpigmentation of underarm skin. Groin and back side of neck. And skin under breast. Skin is black, velvety. My skin tone is wheatish. Please advise me a best treatment. I get up late.. I do evening and night duty. Eat lot of junk food. Bread, cheese, deep fried. Veg nonveg both. I drink 1lit water every day. I have gained excessive weight. I have huge belly fat. My doctor says my right weight is 52-53kgs. Now my weight is 70kgs. Im trying to reduce it by diet and daily exercise. Bt i want even skintone throughout. Please suggest a good treatment. I can't wear sleeveless tops due to dark underarms. I look swollen due to unhealthy weight gain. Im going to get married soon. I don't want such awkwardness. Please help me. Thanku.