Rev 19:20; And the beast was seized, and with him the false prophet who performed the signs in his presence, by which he deceived those who had received the mark of the beast and those who worshiped his image; these two were thrown alive into the lake of fire which burns with brimstone.
Rev 20:10; And the devil who deceived them was thrown into the lake of fire and brimstone, where the beast and the false prophet are also; and they will be tormented day and night forever and ever.
Rev 20:14; Then death and Hades were thrown into the lake of fire. This is the second death, the lake of fire.
OK, so those verses mention Satan and the beast... but what about other people?
Rev 20:15; And if anyone's name was not found written in the book of life, he was thrown into the lake of fire.
Rev 21:8; "But for the cowardly and unbelieving and abominable and murderers and immoral persons and sorcerers and idolaters and all liars, their part will be in the lake that burns with fire and brimstone, which is the second death."
OK, so some are thrown into the Lake of Fire, does that mean they cease to exist?
Rev 20:10; And the devil who deceived them was thrown into the lake of fire and brimstone, where the beast and the false prophet are also; and they will be tormented day and night forever and ever.
This verse says they are tormented day and night forever and ever.
Rev 14:9; Then another angel, a third one, followed them, saying with a loud voice, "If anyone worships the beast and his image, and receives a mark on his forehead or on his hand,
Rev 14:10; he also will drink of the wine of the wrath of God, which is mixed in full strength in the cup of His anger; and he will be tormented with fire and brimstone in the presence of the holy angels and in the presence of the Lamb.
Rev 14:11; "And the smoke of their torment goes up forever and ever; they have no rest day and night, those who worship the beast and his image, and whoever receives the mark of his name."
This verse also says anyone who receives the mark of the beast will be tormented forever and ever, they have no rest day and night.
There are a few more verses I could add to this, if you like.