Hi, Kathee —

No. The Catholic Church has always emphatically taught that the gospels are historical and recount the actual accounts of Jesus's life. Consult the Pontifical Biblical Commission document, "The historicity of the Gospels" [Catholic-Resources] (April 21st, 1964). If you don't believe the Gospels are historical, there is no point in being Christian, much less Catholic. (Not that their historicity can't be vigorously defended.)

The Church wouldn't go to the wall for the book of Jonah in the same way, although traditionally it has been regarded as historical.

But you should not take what your priest says at face value. Just because he says Jonah is fiction doesn't make it so. But if it were fiction, it would not really affect our faith.

Eric