Chapter 1 of Genesis, and especially Gen 1:6, along with dozens of confirming verses elsewhere, depict the world as flat, under a hard dome, underwater....
Never!
"World" in Hebrew, is sphere/globe. The "world" cannot be "flat" because from the beginning it is a "globe". A globe is not possibly ever even imagined to be "flat" nor depicted as such by the Creator from the beginning.
The circle of the earth is "circling" it in the beginning, when the light is separated from the darkness, and the evening and the morning is one "Day".
The heavens are not even named "heavens/two waters", until the expanse is stretched out between the divided in two waters of the created globe, on day 2 of creation week.
The waters are still above the heavens that were cut off the waters below the heavens, and they still circle the earth with the heavens; and in the created heavens the stars, sun, and moon run their own peculiar paths/courses in the circle of the earth/the heavens.
That is what the Word teaches and confirms by multiple verses in many passages referred to by the prophets of God.
heavens are created circling the globe on day 1, then the heavens are expanded out from the waters of the globe, which are divided in two, and the expanse is stretched out under the waters and above the waters
The separation of the light from the darkness depicts the revolving circle of the earth, creating evening and morning/one day.
The world is the globe of water, in Genesis 1.
There is no "earth underwater", in Genesis 1. The earth is not formed out of the elements created in the waters of creation until day 3 of creation week, and it does not exist but in elemental forms in water, until day 3, and is not even named "earth", until day 3, when the waters of creation that are remaining under the heavens are commanded to be gathered together in one place, and the "dry" to appear out of that process, as one mass of "dry", which the Creator then names "Earth".