How to stop this and change the way I am?

Ok my patents divorced and moved in with my grandma and me and my mom and brother and after a while we wanted to move so we moved to a bigger house and I've noticed Ives changed a little I started getting everything I want and my room waz filled the most from the rest and I just started being selfish and less caring for others I really didn't wanna turn out like this I think I'm spoiled and I wish I could stop acting like that and be more of a real person is there a way I can change and be more non selfish and more caring I just sometimes wish I can throw everything away and just be poor idk wat to do I wasn't like this before :(