The very first verse in God's written word is a statement that tells us plainly that the Genesis equation is the beginning of it all. "In the beginning God created the heaven and the earth" (Genesis 1:1).
Before examining the many differences in the ideas about the origin of the universe, it is necessary to ask the question, "How do we determine when the beginning actually began? Modern science does not agree with the Book of Genesis. Modern scientists who are against the Bible, agree with most of the myths and legends about origins. But there is a Book that is the Book of beginnings called Genesis, that makes it clear when the beginning started.
Scientists who are committed to naturalism do not believe in any type of supernatural agency or event intervening in the development of the universe. Such scientists are at least consistent in their atheistic explanations.
All of the "creation" stories other than the Genesis record suggest that there was eternal matter in some form. Some think that the primeval form was water, while others speak of various eternal "gods" or "forces" of some kind. Modern naturalistic science tends to embrace talk about an unimaginable dense "speck" (some form of hydrogen mass-energy) from which the present universe formed after this speck exploded (Big Bang). Of course, no one really knows if that was so, but something has to be the "source" from which all that exists has originated.
The only means of really knowing anything about "in the beginning" is by revelation. God was there. He knows. No human scientist or historian was there when the universe began.
"In the beginning was the Word and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made by him, and without him not any thing made that was made...And the Word was made flesh and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father), full of grace and truth" (John 1:1-3,14).