It is hard to say what foods are available in your region of India along with foods restricted by your religious beliefs. These Google search results should help you find the answer to your question, especially in the last two links.
http://tinyurl.com/indian-diet
http://tinyurl.com/indian-nutrition
http://tinyurl.com/indian-glycemic
http://tinyurl.com/indian-vegetarian
I am also a vegetarian and found I had to make some drastic changes in my diet, but I am now able to eat a variety of foods and enjoy cooking again. What you need to reduce is your intake of carbs. If you are used to eating a large amount of rice (for me the problem was pasta) you will have to change that. We are all different so I suggest you learn to "eat to your meter" which means trying various foods then testing your blood sugar two hours after eating and seeing how much it has gone up. Some people do better with whole grains such as brown rice, for some it makes little difference and they can only eat about 1/2 cup of cooked rice (not much). All vegetables are good, though the more starchy ones such as potatoes are a problem. What do you eat for protein? Me, I eat a lot of cheese which I think is not part of the traditional Indian diet. Nuts are excellent as is nut butter. Beans and lentils, again, have to be limited in quantity...test, test, test. Things with flour also have to be limited in quantity (like the wonderful Indian breads). Ditto for fruits. Anything high in fiber is better as it reduces the usable carbs. Soups are good. I eat eggs for breakfast with one piece of bread. There are sites that list the carbs of various foods like calorieking.com