This phrase is used here to mark the beginning of a new part of the story. If your language has a way for doing this, you could consider using it here.
"the women bore daughters"
Translators could add a footnote saying: "It is not clear whether this refers to heavenly beings or human beings. In either case, they were beings that God created." Some believe these words refer to angels who rebelled against God, that is, evil spirits or demons. Others think this may refer to powerful political rulers, and others think this may refer to the descendants of Seth.
Here Yahweh is talking about himself and his spirit, which is the Spirit of God.
This means that they have physical bodies that will one day die.
These seem to have been giants, very tall, large people.
"The Nephilim were born because"
See how you translated this in Genesis 6:2.
"These Nephilim were the mighty men who lived long ago" or "These children grew to become the powerful fighters who lived long ago"
"famous men"
"everything their hearts wanted to think about"
"their inner, secret thoughts"
"he was very, very sad about it"
"I created mankind. I will destroy mankind ... so that there will not be any people on the earth"
"completely destroy." Here "wipe away" is used in a negative sense, for God is talking about destroying the people because of their sin.
"Yahweh looked favorably on Noah" or "Yahweh was pleased with Noah"
See how you translated this in Genesis 5:21.
"Noah had three sons" or "Noah's wife had three sons"
Translators may add the following footnote: "The sons are not listed in the order in which they were born."
Possible meanings are 1) the people who lived on the earth or 2) "The earth itself."
"was rotten" or "was completely evil"
Possible meanings are 1) "in God's sight" or 2) "in the presence of Yahweh"
"and there were very many violent people on the earth" or "because it was full of people who did evil things to each other"
The word "behold" here alerts us to pay attention to the surprising information that follows.
Possible meanings for what "all flesh" represents are 1) all human beings or 2) all physical beings, including humans and animal.
"had stopped living the way God wanted" or "had behaved in an evil way"
See how you translated these words in Genesis 6:12.
"people everywhere on earth are violent"
"I will destroy both them and the earth" or "I will destroy them when I destroy the earth"
This refers to a very large box that would be able to float on water even in a very bad storm. "a large boat" or "a ship" or "a barge"
People do not know exactly what kind of tree this was. "wood used for building boats" or "good wood"
"spread pitch on it" or "paint tar on it" or "cover it with pitch to make it waterproof"
This is a thick, sticky or oily liquid that people put on the outside of a boat to stop water from going through gaps in the wood into the boat.
A cubit was a unit of measure, a little less than half a meter long.
"138 meters." or you may also write a footnote that says: "Three hundred cubits is about 138 meters."
"twenty-three meters"
"fourteen meters"
This was probably a peaked or slanted roof. Its purpose was to protect everything in the ark from the rain.
"a lower deck, a middle deck, and an upper deck" or "three decks inside"
"floor" or "level"
God said this in order to emphasize that he would do what he was about to say. "Pay attention" or "Listen to what I am saying"
"I am about to send a flood of waters" or "I am about to cause a flood"
Here "flesh" represents all physical beings, including humans and animals.
"that lives"
"make a covenant between you and me"
with Noah
"You will enter the ark." Some translations say "You will go into the ark."
"You must bring into the ark two of every kind of living creature"
an animal God created
"of each different kind"
This refers to small animals that move on the ground .
This refers to two of every kind of bird and animal.
This refers to Noah and so is singular.
"so you can keep them alive"
These refer to Noah and are singular.
"So Noah did everything that God commanded him to do"