Hi!
To bulk up, you need to focus on muscle gain. From diet point of view, make sure you have enough protein in your diet. And focus on strength training.
So basically, your protein intake would depend on the intensity of your workout. You have to have good sources of protein which include dairy mostly, considering you are a vegetarian. So include good amount of paneer, yogurt, skimmed milk in your diet. You can also have tofu and soy beans or chunks a few times each week.
In case your needs are not fulfilled with dietary protein, you might need a supplement. But to be sure about that, I would need more details.
Next Steps
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