He was pope nearly 25 years.
The Pope will hold office until their death or they become incapacitated or if they abdicate (Choose to stop being pope).
The pontificate of Adrian VI lasted just over a year. He reigned from January 9, 1522, to September 14, 1523.
The Catholic Church has had popes for nearly 2000 years, since Jesus Christ appointed St. Peter the first Pope.
Pope John Paul II was pope for 25 years.