>>76999144actually satan originally was just a hebrew title that meant accuser and was basically a role that was taken on and lucifer is just a latin word that means 'shining one/star' and was originally used to refer to metaphorically refer to the king of babylon in the old testament
Only in the new testament did the writers like Paul decide to invent the character of Satan/Lucifer and conflate it all together into one entity and to mistakenly think the 'fallen from heaven like a star' thing was actually literal and talking about this one angel character
tl;dr Satan/Lucifer never actually existed until right at the end of the Bible (the snake in Genesis is never actually referred to as the devil, it's literally just a random talking snake until the retcon by Paul and whoever wrote Revelation)