Genesis 5:21

21 When Enoch had lived 65 years, he became the father of Methuselah.

Read Genesis 5:21 Using Other Translations

And Enoch lived sixty and five years, and begat Methuselah:
When Enoch had lived 65 years, he fathered Methuselah.
When Enoch was 65 years old, he became the father of Methuselah.