Elves: Angels. They are superhuman in their understanding and abilities and they can choose to leave middle earth unlike the other races.Orcs: Demons. They are a race of elves abused, corrupted and changed by Sauron.
If you go by the books, Maiar and Valar == angels. Known examples in Middle Earth are Gandalf, Saruman, Radugast, Sauron and maybe the Balrog.
Sauron: Satan.
Morgoth == Satan
If you go by the book, it’s Gandalf, not Gondalf.