what anal sex feels like? Is if sore?

It depends on you. If you are relaxed and allow things to proceed slowly, with copious amounts of lube it can be quite exciting. If you tense, use to large an object as you learn, or jump off the deep end and use an actual penis to learn (far to large an object to start with) you risk serious pain and possible injury. Go to your local sex shop and they will be very happy to sell you a kit that will take you from day one learning to where you are ready for a mans penis, even a very large penis.