So, which parts are literal and which are poetry?
first of all, there are other types of writing as well.....historical documents, epistles (letters), wisdom literature.....Hebrew poetry that originates from stories told around the campfires at night are generally noted by particular Hebrew word typically translated into the English word "Now"......
note the wording of Genesis 1
1 In the beginning God created the heavens and the earth.
2 Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.
3 And God said, “Let there be light,” and there was light. 4 God saw that the light was good, and he separated the light from the darkness. 5 God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning—the first day.....etc.
The verb tense of Genesis 1:1 is different from that used in the rest of the passage......verse 2 begins with "now".....they are actually two separate pericopes.....
Verse 1 is actually an imperative, a command.....in the sense of "Understand this!"......In the beginning God created the heavens and the earth.....
Verse 2 begins a depiction of creation in the fashion of a story teller speaking at night around a campfire, after supper.....that pericope ends with 2:1....
the balance of Chapter 2 is in narrative form.