No, he was Governor of New York State. (New York city has a mayor, not a governor.) No, cities do not have governors. They have mayors. Thomas E. Dewey was the 47th Governor of New York State. He served from 1943 to 1954.
It is said that the 1st governor in New Jersey colony in the 1600s to 1700s was Andrew Hamilton. He 1st became governor of East Jersey in 1687. Later on, he became governor of also West Jersey in 1692.
New York colony had a number of rulers, but the first leader was GOVERNOR STUYVESANT who was the Dutch governor of New Amsterdam, which is what New York was called before being transferred to the British.