When it says it’s allegory, such as in Galatians 4:24, it’s allegorical.
When the symbols are explained, such as in many of the parables, it’s allegorical.
If there is a valid reason for believing Genesis is allegorical and there is a coherent explanation of the symbolism, I’d love to hear it. (Atheistic philosophy labeled “science” isn’t a valid reason.)
What are the trees of life and the knowledge of good and evil for 500, Alex.