To answer the question, “What about Revelation 20:10 which says the devil and the beast and the false prophet will be tormented forever?” They will indeed be tormented forever; however they are not humans. Jesus says Gehenna (hell) was specifically made for Satan and demons (Matthew 25:41), however fire does not affect angelic beings like humans. (see Ezekiel 10:7).
Additionally, the word “tormented” here is the same Greek word that speaks of Lot being tormented in 2 Peter 2:8 watching the bad behavior of the Sodomites. The same Greek word is used for both Lot and Satan being tormented.
Also, John himself tells us where the beast comes from “the beast that ascendeth out of the bottomless pit” (Revelation 11:7) This “beast” is not a human being. Humans do not come out of this pit. The apostle John wants us to know this beast is a demon by telling us his origins.
NOTE: When the devil or the beast and the false prophet were thrown in the lake of fire, we read no word about a second death. However, when human beings are thrown in there, it says second death.
Dirk Waren has some keen insight on this verse:
Adherents of eternal conscious torture often cite the above text, Revelation 20:10, to support their view by suggesting that “the beast and the false prophet” are human beings…The antichrist is indeed a human being…However, “the beast” from Revelation 19:20 and 20:10 is not referring to this man, but to the evil spirit that possessed him. This is clear because the bible plainly states that the beast originated from the Abyss (Revelation 11:7 and Revelation 17:8). “The Abyss,” according to scripture, is the furnace-like pit where evil spirits are imprisoned, not human beings (see Luke 8:31; Revelation 9:1-2 and Revelation 20:1-3)…Likewise, the false prophet is referred to as “another beast” (Revelation 13:11-17, Revelation 16:13 and Revelation 19:20). The Greek for “another” here is allos (al’-los), which means “another of the same kind.” Therefore, the false prophet is an evil spirit that originated from the Abyss as well.
For further proof that the beast and the false prophet are evil spirits and not human beings, consider Revelation 16:13: “And I saw three unclean spirits like frogs come out of the mouth of the dragon (Satan), and out of the mouth of the beast, and out of the mouth of the false prophet.” First of all, notice that the beast and the false prophet are spoken of on a par with the devil himself here; this signifies that they are evil spirits…
Again, I even heard Dr. Tony Evans (who holds to the Traditional position) describe the final home of the devil as an island in a lake of fire. This will be Satan’s home forever…his jail cell.
However, humans are destroyed there (Matthew 10:28).