So if some parts of the Bible are meant to be taken literally and other parts are NOT meant to be taken literally, how do we determine which is which?
By reading like you'd read other involved, complex books, to get the real situations -- that in order to understand a sentence or paragraph somewhere correctly, you must have read what is before it, the previous parts of that book, for each of the books. And more -- some of the books are like a series also, such as most of the early books of the Old Testament. Often the first 5 are grouped together, but actually much that happens in the 6th book only makes any sense from already knowing books 2-5. Altogether, many parts of the first 17 books are cross dependent on other sections in other books, so that to get the real situation in book 6 or book 11 you need to already know book 2-4, and several parts of 7,8,10 etc.
So when you encounter something like the pillars of the Earth cry out (or whatever you are seeing in the text), you know instantly if it is figurative wording
because you've been reading through from the beginning of that book.
Of course, that means to get what's happening a person must really be a reader or get caught up in the whole of it, otherwise they are only in the situation of someone that picks up a random book in the library and opens to a random page and reads a sentence or paragraph without knowing the situation, and then merely has guesses about what is happening.
When people are doing that guessing -- which is also common among believers too -- then they tend to merely read onto (lay on top of) the text whatever they expect or think as their own pet theories.
Since only some people these days read through all (meaning not 40% or 70%, but 98%+), many people are just groping in the dark and having wrong conclusions. That's why you can't rely on some website to tell you what something means, but have to read through yourself fully. And of course sympathetically, so as to get the intended meaning instead of one's own preconception. Having fully read, one can then gauge the accuracy of any commentary in that you will know if the writer of the commentary knows the full text.
For example, if someone thinks Sodom was destroyed because it had gay people or homosexuality in it, then I know with certainty that they have
not read through the Old Testament. Without having read through the OT myself, I wouldn't be able to discern when someone is making up their own pet theory. I'd be at the mercy of people claiming they read a lot (who in reality did not or are poor readers, or are merely parroting claims they saw somewhere and pretending).
Here's a great example -- if you see someone take a phrasing like: " who stretchest out the heavens like a curtain" and then assert it definitely is saying the stars are like a 2 dimensional blanket/curtain, that this is the intended meaning, you know instantly they are lying.
Even if one merely had read only the very next verse, they'd see through that kind of lie.
Psalm 104 KJV
So, just as it is with any believer, anyone in any church, you also won't know what the text means (or have a chance to know) unless you read through full books entirely. They don't know without that, and you won't either.