does anybody knows if there is a website like this for young people who have disabilities
There should be. For both physical and mental disabilities, both visible and invisible disabilities. Sadly, I do not know of any. :/
Search online. There seem to be some sites such as Special Bridge, Disability Match, Wispers 4 U etc. Good luck!
I think they are more specific than the general term "diability"... try typing something like "singles with MS" or whatever