No, there is no age requirement. The only requirements are that the pope be male and Catholic. Should he not be ordained yet when elected pope, he will be ordained and then consecrated as a bishop. Usually, however, the pope is elected from the College of Cardinals, but that need not be the case.
He was elected pope at the age of 76.
He was 78 years of age when he became pope.
There is no age limit.
He was 58 years old when elected as pope.
There is no minimum nor maximum age to be elected as pope.
Pope John Paul II was 58 years old when elected in 1978.
No, the pope is elected with paper ballots.
He was elected in 2005 as pope on the 4th ballot of the conclave.
Pope Paul VI was elected to replace Pope John XXIII.
Pope Francis was elected on the 13th of March, 2013.
Pope Gregory VII was elected pope on April 23, 1073.
Pope Benedict was 78 years old when elected.