My mom died with no will and dad was a thief with hundreds of thousands of dollars

I would appreciate any help with this disgusting situation, I was tricked by my father to get a paper notarized for him to represent my mother in a slip and fall case and I was not even thinking about it but it was a renunciation to be her representative of her estate!! I was just advised by the court, and he was granted letters from the court to her estate and he filed in probate court and I was never told anything about it until I got a joke of a family settlement agreement from his attorney that he is in cahoots with!!he transferred from an account that was in my mother’s name only with over 2hundred thousand dollars in it!! She died 2 1/2 years ago and I was just finding out all of this.. I don’t know what to do with it but it was not done legally? I’m sorry for the rambling but it’s a very bad situation and he is taunting me Location: Pittsburgh Pa.