“In the beginning” [John 1:1]
seems to be the mark of a ‘start‘
–the start of a ‘sequence.’
For more use the DOOR.
Before this “beginning” we know no details, only the notion of “was.”
“In the beginning God” was. We know no more than that. Yet in John 1:1 we learn that the “Word” both “was with” and “was” God. (The Word is commonly considered to be Jesus, the Second Person of the Trinity.) So here we have God (which includes Jesus) as the start of a sequence (before which we know nothing).
The sequence–in Genesis–continues with various steps in the creation of everything, followed by a narrative history. History in books or in rock layers always appears in sequences.
Both science and the Bible can offer some understanding here–in terms of order or times of happening.
Other than speculating about “multiverses”–about which there is no proof–science can offer no help about the “before of before.”
Neither can the Bible.
Except for the declaration that God came first.