Someone on scjm asked the following question:
Mainly for those who think some of the tanach is parable
Tanach parable or historical?
How much is parable & how much is historical?
all parable?
parable up to exodus?
parable to david & goliath?
up to Samson & Delilah?
Discovery of the lost scrolls?

A somewhat remedial question, but one I think worthy of having a thought-through canonical answer. Here is a polished version of my reply:

My own opinion, one Orthodox opinion among a wide variety:

All of it, from “In the beginning” is historical. Much of that history may also be parable; G-d orchestrating an event to teach a lesson.

But.

The story of creation, as it actually occurred, is incomprehensible (to anyone less than G-d). The historical layer of the text is therefore inaccessible to us. I can therefore take whatever I do glean from it and treat it as though it were allegorical, because that’s all of it that I can understand.

To my mind this is entirely true for Genesis ch. 1, ch 2 (the Garden of Eden and the forbidden fruit) is somewhat more comprehensible but still too alien to our post-fruit experience to be entirely taken at face value.

And of course, the visions actually described by the prophets (including but not limited to the Throne vision in Exodus, and the Chariot visions of Ezekiel and Jeremiah) are historical descriptions of visions actually seen, but the visions themselves are allegorical constructions.

(Whether G-d constructs the allegory, or the person’s own intellect wraps the alien into the usual matter of sensory experience, I leave open.)

Last, there is an opinion in the talmud that Job was a parable written by Moses to teach about providence, justice and suffering.

I know many O Jews who would consider my view on Genesis 1 to be too liberal, whether Young Earther omphalists [the universe was created with the illusion of age] or believers in a history before this world [invoking Bereishis Rabba]. I also know a few on the left edge who would consider everything up to Abraham as allegory.

Technically, the only bit that definitionally being Orthodox requires you to believe is historical is the exodus; the events commemorated in the holidays and we are commanded to remember daily; or the books of Exodus through Deuteronomy — and I’m not even sure every detail of those. There are only 13 mandatory beliefs, and the historicity of Abraham isn’t actually one of them. But I never encountered an Orthodox-affiliated Jew whose beliefs are anywhere close to that level of minimalism, and most of us would consider him very misguided (or mistakenly brand him a heretic).

Then there are iffy bits, like Maimonides’ belief that the three angels visiting Abraham, Bilaam’s donkey, and any other story in which an angel is seen or heard, must be prophecy. (Angels aren’t physical, so how can they be seen or heard outside of prophecy?) Not that many O Jews know of his opinion, but those that do can’t consider its rejection “mandatory”.

One last omission from the discussion: Idiom isn’t metaphor. G-d’s “Hand” is an diomatic expression about His Might. The “anger of His ‘Nostrils'” is an idiom based on the human response of flaring nostrils when angry; not a parable.