Don’t think that if you get your score to 1600 that it moves you to the front of the line. It certainly helps to have a high score, but many students with perfect scores and GPAs still aren’t accepted to the top schools. There just aren’t enough spots.
I don’t think applying to the 20 schools on your list is a good use of your time as each application takes a lot of time and energy and some on your list you really don’t have a good chance at. Pick a few, then use your time for other research and applications.
What options do you have in India, Australia, Canada, or Europe? We are all just suggesting you have a Plan B or know that you may have to take a gap year. You don’t want to stay in India but you may not have another option if you don’t plan for one.