Funny enough, if Satan wanted people to not be on God's side, he'd encourage them to read the bible.
All the awful things in the bible were caused by God, not Satan.
The ONLY reason why Satan and demons are disliked by God is because they are defectors. They didn't do anything bad other than say, “we don't like this guy, and you probably shouldn't, either.”
When I was younger, I remember asking why Satan was "bad". And they gave me all sorts of interpretations like he tortures people and he lives in the firey hells. And I kept pointing to bible stories where God does the same damn thing.
The worldbuilding is very shoddy because too many authors worked on the canon over far too long a period. Even accounting for the "New Testament" sequel, it's retcons on top of retcons. The "Islam" spinoff at least managed to start with a clean slate, despite several callbacks to the prequels.
I believe "the satan" literally means the accuser.
I think there's kind of two concurrent perspectives: one of Satan being an evil being, trying to corrupt people away from truth, life and the worship of God; the other of Satan as an accuser and tester, bringing into view and actuality the evil that's in people's hearts/lives.
I believe the 'official' interpretation would be that there's elements of both, and the full truth about the satan is more nuanced/profound than we've yet understood.
There's a view that Satan created the earth and is good, God is evil and the bible is a lie.
There's a view that only Satan is real. God is made up to give people hope when there really isn't any, either made up by deluded people or Satan himself.