The Lake of Fire is the final destination of anyone whose name is not found written in the Book of Life at the end of the Millennium (Rev 20:15). The fire in this lake is God’s Consuming Fire that burns up everything that offends Him. Once thrown in the Lake of Fire, the soul of that person will cease to exist and will be blotted out from all memory and all records. It will be as if those souls had never existed.
At the return of Jesus, at the 7th trump, the false prophet (antichrist, satan’s physical form) and his beast system (satan’s spiritual influence) will be thrown into the Lake of Fire (Rev 19:20), and this will leave only the last part of satan’s trinity, satan in his basic form, which will be bound and locked away in the pit until he is released one last time at the end of the Millennium (Rev 20:2-3).
The beast and the false prophet are all that will perish in the Lake of Fire until the end of the Millennium, at which time anyone who is not found in the Book of Life will also be destroyed in the fire (Rev 20:15). This is known as the Second Death (Rev 20:14). The First Death is the death of the flesh body, and for those who have not yet overcome, it is the spiritual death of those people, which means that the spiritual body becomes spiritually dead, or liable to die (in verses about the Millennium, these people are often referred to as the dead, such as Eze 44:25) and therefore they become mortal souls. This is as opposed to the First Resurrection, which is experienced by those who have overcome by the time of the return of Jesus (Rev 20:4-5). Those who go through the First Resurrection receive immortal souls from the beginning of the Millennium (Rev 20:4) and will be guaranteed eternal life and will not have to worry about the Second Death (Rev 20:6).
Those who pass the test at the end of the Millennium will experience the Second Resurrection. These will then also have immortal souls and will enter into the Eternal Kingdom of God, or Third Earth Age (Rev 21-22).
At the end of the Millennium, death and hell will be thrown into the Lake of Fire (Rev 20:14) and these negative things will no longer be remembered entering the Third Earth Age (Rev 21:4). Though most believe that those who are sentenced to the Lake of Fire will suffer forever, this is actually a mistranslation from the Greek ‘eis aion aion’, which means ‘until the end of the age’, loosely translated. In the Eternal Kingdom, no one will know death, or pain, or sorrow, or suffering. There will only be love and happiness.