Need your height to assess the case better. Further, we need to understand the cause of underweight like Irregular or improper food habits Lifestyle issues Intestinal and gut related issue Heridity Exercise related etc.. Once we know the cause we can work towards right weight gain. It's imperative to understand difference between general weight gain and fat gain. You need to focus on muscle gain and not mere fat gaim

What's your height? Take high protein diet and balanced nutrition and do exercises Contact me through practo direct consultation

Eat more natural carb foods like white rice, potatoes, sweet potatoes, bananas, milk and milk products like butter, paneer & ghee.

Take high protein diet. Ask me directly for customized diet plan for you

Hi, surely will help you. See, there are many reason of not gaining weight. . Endrocrine problems . IBS . Dietary problem . Liver problem . Tuberculosis . Vitamin and minerals deficiencies . GI (Digestive)problem . Improper sleep . Stress And many more HOW WE TREAT Underweight thru DIET . Find the main cause and Deficiency which cause hidderence in weight  gain . TREAT the cause first. . Increase your appetite . Reduce the Deficiencies occurring in the body thru diet . And at last you will easily gain weight without much effort. So, better to consult through the link below,so that  we can discuss in detail and suggest you accordingly.

Diet & exercise together will help you to gain weight in right way. I can give you a tailor made diet plan