hello!!! welcome to health care site...your weight problem is not a big issue.
here are some tips you can follow them easily .
Milk is the best food which will help in rapid weight gain,Milk is a biologically complete food, which makes available all the amino acids that helps to build muscle.
Dry fruits are ideal for people who wish to put on weight. They have a high calorific value and are very good strengthening & fattening foods.
Regular exercise is extremely crucial in the management of optimum weight. Activity and exercise stimulate the digestive processes, aid in proper elimination, and boost appetite.
Intake of foods like cereals, legumes, dry fruits, bananas, mangoes, milk, fish, egg whites. These food are a rich source of carbohydrates, fats and proteins
and will help you to put on weight & look attractive..