Why don’t you get off your high horse and tell me who did the sons of Adam and Eve marry?

Up until now (several pages of) answers and replies to you have been simple logic and deduction essentially IF -> THEN statements. However, I am not wise enough to answer these last questions in the same definitive manner. The best I can do is share my opinions on these issues. Perhaps that will be helpful.

On the question of Adam and Eve I believe the Bible/Torah is best understood as a functional document. It's intent and purpose is to redeem and rectify humanity.

For this to occur biblical wisdom must be conveyed in a manner that is both simplified enough to be understandable by primitive man while simultaneously accurately reflecting a truth which can be better understood as our wisdom grows. The best way to meet these two needs is via parable and metaphor.

(The reasoning below represents my opinions and speculations on these issues. I make no claims beyond that)

Adam and Eve in the garden can be looked at literally as a man and a woman walking through a garden and considering the fruit of various trees.

Or Adam and Eve can be looked at as a metaphor for our biological species progenitors. All choices were potentially open to our remotest ancestors but a singular choice namely the development of an intellect capable of understanding good and evil was "forbidden" as that choice is probably incompatible with long term sustained biological existence.

Many "punishments" outlined in the Bible are not necessarily outside intervention at all but simple cause and effect the inevitable consequences we bring upon ourselves from sin.

Let's look at the "punishment" women received as a result of eating the fruit from the tree of knowledge.

Genesis 3:16
"Unto the woman He said: 'I will greatly multiply thy pain and thy travail; in pain thou shalt bring forth children"

Why is childbearing in humans so painful? A religious man would have told you 1000 years ago that it was because Eve ate from the tree of knowledge. It has taken science a very long time to catch up to this very simplified but according to our current theories essentially accurate description.

Current science theory states that the reason human birth and labor is so painful and dangerous is due to the physiological consequences of our large brains specifically some combination of the physical limitations of pelvic size when walking upright and the extreme metabolic demands a large infant brain places on a mother.

See:
Why Is Human Childbirth So Painful?
https://www.americanscientist.org/article/why-is-human-childbirth-so-painful

For the most part God doesn't punish us we punish ourselves with our choices. Sometimes these "choices" were made long before our time but the consequences nevertheless impact us.

Now unlike my prior posts which were simple logical deduction the arguments in this reply are opinion. They are one possible interpretation. I have not proven this opinion is fact and am not in a position to do so currently. I share them as a potential answer to your questions but the question is a spiritual ones and must ultimately be answered on a personal and individual level.