During the 7 Years, Satan will indwell the evil world leader who will deceive humanity into taking his ‘mark’ so that they can feed their families, do commerce, survive, and will convince people will to worship them.  There will also be another evil man, the False Prophet, who will do many tricky miracles and use his lying influence to convince people to worship the evil world leader and Satan.  At the end of the 7 Years, Jesus Christ will return to earth and will defeat the Antichrist and the False Prophet and will throw them into the Lake of Fire.  Satan, the Devil, will be chained for 1,000 years in the Abyss.  After the 1,000 years, he will be released and will influence some, but ultimately will be thrown into the Lake of Fire as well forever.