Well I have a rabbit and they are awesome. I don't mean to be mean but you should have found out about rabbits before you brought one home. Alot depends on the breed and size of your rabbit. I have a dwarf rabbit. If the rabbit is under a year you should give them pellets, no extras added and alfalfa. When they are over a year gradually take away the alfalfa and introduce timothy hay. Also cut down on the pellets and start giving it rommaine lettuce. Don't give it regular lettuce because it has no nutritional value. The amount you feed depends on the size on the rabbit. Good luck! You will love rabbits!!!
Go to rabbit.org. It is very informational!