As they say, practice makes perfect. If you practice something long enough, you get better by the minute. If you dislike volleyball a lot, you should try other sports until you feel comfortable. Also I suggest you get some friends to play with so it makes it easier. Also, don't worry about the comparing part, I know someone who got compared to a rock and about how much better the rock does its job.
You don't really need to play a sport, your parents probably would just like it if you went outside and played games with your friends. If your parents do want you to play a sport you could always fin a non-competitive team or just tryout for school teams (if your on a team you will be much more "fit" and In shape)
You can keep practicing. Even the best athletes started out the same way you did. You're not the only one who isn't good when they first start. Keep your head up but keep practicing or maybe try soccer or cheerleading.
Sounds like you have terrible parents. I would keep my head up, keep writing, and screw sports if you dont like them. Dont ever let someone make you feel bad just because you arent good at it.
Join soccer its fun and easy