My hamster has green stuff on its leg and bell y what should I do

I suggested earlier that you take it to the vet. You said your mother won't do that. Short of going to the vet, it could be some form of Wet Tail but that is still pretty much only treatable by the vet. If you can't or won't take the hamster to the vet, there is nothing anyone here can really do for you so asking over and over will not yield any better results for you. I am sorry your hamster has this problem, I know it is hard to deal with but at this point, I think only a vet can help your hamster. Sorry. Good luck and I hope everything works out.