During the 6th creative period, Elohim created the human race, both male, and female (Genesis 1:26-27). God says to “them” to “Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion… over all the Earth”
Genesis
Were Cain and Abel Twins?
I have read many times that Cain and Abel were possibly twins. I think it is within reason to infer that they were twins. This comes from (Genesis 4:1-2).