... where the waters in Gen 1:2 came from,...
Very simple. The waters were created by God on the first day.
Gen. 1:1-2 says:
1In the beginning God created the heavens and the earth. 2Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters.On the first day, God created the heavens and the earth.
Don't think that the earth was nothing but dry land on the first day. When God created the earth, the earth already had land and water. But the land was under the water; and it was only on the third day when dry land appeared.
Here's what happened on the third day, according to Gen. 1:9-10,13:
9And God said, “Let the water under the sky be gathered to one place, and let dry ground appear.” And it was so. 10God called the dry ground “land,” and the gathered waters he called “seas.” And God saw that it was good. ... 13And there was evening, and there was morning—the third day. ... or how night & day came to be about (Gen 1:3-5) before the Sun and the stars (Gen 1:16)...
This is for more advanced study.
On the first day, God made light, and separated light from the darkness. This was the temporary light to be used prior to the creation of the sunlight, moonlight, starlights, etc.
On the fourth day, God made the sunlight, moonlight, starlights, etc., which were the permanent lights. Upon creation of the permanent lights on the fourth day, the temporary light created on the first day ceased to exist.
... or whether animals came before Man (Gen 1:20-27) or whether Man came before animals (Gen 2:18-20)
Those are verses commonly cited to point out alleged inconsistencies in the bible. But there is no inconsistency there.
Gen. 1:20-27 is chronological. Animals were created before man.
But Gen. 2:18-20 is not chronological. It was not stating a chronology of creation, because that had already been stated in previous verses. It merely explains why Eve had to be created:
18The LORD God said, “It is not good for the man to be alone. I will make a helper suitable for him.”
19Now the LORD God had formed out of the ground all the wild animals and all the birds in the sky. He brought them to the man to see what he would name them; and whatever the man called each living creature, that was its name. 20So the man gave names to all the livestock, the birds in the sky and all the wild animals.
But for Adam no suitable helper was found. 21So the LORD God caused the man to fall into a deep sleep; and while he was sleeping, he took one of the man’s ribs and then closed up the place with flesh. 22Then the LORD God made a woman from the rib he had taken out of the man, and he brought her to the man. God said there was a need to create a suitable helper for Adam. Why? Because none of the animals previously created was considered a "suitable helper" for him. So God created Eve --- the "suitable helper".