Fetching details from the dictionary...
how many years; how long
what year
何年かかっても夢を諦めない。
I won't give up my dream no matter how many years it takes.
ここに住んで何年になりますか。
How many years have you been living here?
何年ぶりかの再会を喜び合った。
We rejoiced at our reunion after many years.