Thank you for choosing HCM
See if you want to gain weight the basic theory is eat more than what you burn off. So a high calorie diet ( high protein) , eat plenty of fresh fruits , stay hydrated, you can also take a protein powder and add a multivitamin
to your diet. Since you are vegetarian i would ask you to get the protein powder to supplement your daily protein needs.Follow this for a couple of months and you should be on your way .
Thank you and take care