2 Thessalonians 2:6-8 nkjv
6 And now you know what is restraining, that He may be revealed in his own time.
7 For the mystery of lawlessness is already at work; only He who now restrains will do so until He is TAKEN out of the way.
8 And THEN the lawless one will be revealed, whom the Lord will consume with the breath of His mouth and destroy with the brightness of His coming.
The restrainer is the Holy Spirit, who lives in believers. Once He is taken in the rapture, then the lawless one will be revealed. We also know that there will be a literal person known as the Antichrist.
1 John 2:18 nkjv
Little children, it is the last hour; and as you have heard that THE Antichrist is coming, even now many antichrists have come, by which we know that it is the last hour.
Many antichrists have come, but THE Antichrist will not be revealed until after the rapture. I hope this answered your question, and If there is something else you want to know, feel free to ask.