Clearly you don't find him attractive physically and you both lack bedroom chemistry. You say that you try to keep him happy but are you really sure if he is having a good time with you in bed? According to me, most Indian men like good sex. Doesn't mean we are good lovers or know how to please a woman. Also, his being a virgin means he really has no idea about your expectations, since he never had any experience before. May be he is assuming that you are not interested in sex and the entire sex thing is just for him. I don't know. I think there is a lot of assumptions going around here, on both sides, which are affecting your sex time.
Communication is the key here. But in Indian contexts it does become difficult to start communicating about such things. I am not sure if giving more time is going to work here because if he is thinking that your are not interested in sex than there is not going to be much effort from his side. You need to fix this first.
Try being a little more open towards him and take the initiative. Make him look forward to sex and let him enjoy. Make sure he notices that you enjoy it too. Be patient if things are still not upto your expectations initially and don't make your frustration apparent to him. Key is you need to build up his confidence. Every man feels happy and good about himself when he is able to please the woman in bed.
About you not feeling attracted to his body, give it some more time. Sex is just not about physical looks. That becomes secondary when you both start connecting at a deeper level during sex. I had some issues with my girlfriend as she was a little bit on the heavier side. But once we started enjoying our time together I barely even notice it anymore. You both start figuring out what the other guy likes more and it starts happening without anybody even saying anything.
Its good that you are thinking objectively about it and are seeking help instead of just accepting the status quo. Sex is an important part of relationships when you are young and you should try whatever it takes from your end to make sure you get it right.