abraham is a mythical character and not an actual person. sumerians lived inmesopotami not the levant. the peopole of the levant no matter how much switching around you do were caucasians,which means they were probally white people and that includes the cannites.
the exodsu story is mythical also and there is no archeological basis or even written down by kemetians accounts.
i have never heard any scholar caleld the ancient sumerians black and for the most part their art work does not look africoid.