I am being sued by my brother over a propery in the U.S I lived there at the time the matter was setteled through
Mediation by friends. I moved to Canada and he is suing me for $700,000. His claim is based on he said she said.
He is a US citizen all the witnesses live in the U.S.

I am being sued by my brother over a propery in the U.S i lived there at the time the matter was setteled through
mediation by friends. I moved to Canada and he is suing me for $700,000. his claim is based on he said she said.
he is a US citizen all the witnesses live in the U.S.

You don't really think anyone can give you any useful advise on the basis of those 5 sentences, do you? You need to retain an attorney in the U.S. state in which you are being sued.