There is no way to understand the Bible without understanding the book of Genesis.
Genesis 1:28-- And God said to them, “Be fruitful and multiply and fill the earth and subdue it and have dominion over the fish of the sea and over the birds of the heavens and over every living thing that moves on the earth.”
Were Adam and Eve celibate before the fall? Apparently yes,but why ! If I am not mistaken, Tradition holds they had lived in the garden of Eden for several years.So why haven't they reproduced during this time? What were they doing the whole day?