autistic grandson

want some advice on where to go to find help for my grandson and myself. all we seem to do is annoy each other he is in secondary school in year 7 when first medicated everything was fine but as he gets older and mixes with older children he has become very mouthy and the language is discussting i suffer with depression and its like being bullied and we dont go anywhere or do anything together aanymore and being stuck indoors because of covid has made life miserable please anybody suggest anything to help.