I couldn't find a lot about it on the internet (I was not sure about the right keywords).
To be clear, I'm asking if it is all or most religions, be ancient or modern, that are based on the concept of Good VS Evil. Furthermore, is "Satan" - or whatever you want to call him - as a personified Evil present in most/all of them? Thank you.
Not really, I can link to some earlier answers that might be helpful here. In Ancient Greek belief, the gods often did immoral or unjust deeds and some were both feared and disliked, but they were still worshipped as u/Spencer_A_McDaniel describes here and u/KiwiHellenist does in this thread. There have also been some answers that discuss how Zoroastrianism, typically described as a "dualist" good vs evil religion, developed throughout its history, like this by u/lcnielsen and this by u/Trevor_Culley