Yes, the devil will be burnt to ashes, and will never more be around to tempt and torment us. The passage below talks about him, and how he ends up.

Ezekiel 28     ¹⁴ “You were the anointed cherub who covers; I established you; you were on the holy mountain of God; you walked back and forth in the midst of fiery stones. ¹⁵ You were perfect in your ways from the day you were created, till iniquity was found in you.

¹⁸ “You defiled your sanctuaries by the multitude of your iniquities, by the iniquity of your trading; therefore I brought fire from your midst; it devoured you, and I turned you to ashes upon the earth in the sight of all who saw you. ¹⁹ All who knew you among the peoples are astonished at you; you have become a horror, and shall be no more forever.”’”

The devil cannot read your mind unless you give yourself to him. He can, however, plant thoughts in your mind so cunningly that you think they are your own thoughts. 

As far as this bargain with the devil, which you seem to be very concerned about, don’t even think about it. If you accept God fully, if you give your entire life to Jesus and accept Him as your Saviour, every sin can be forgiven, and God protects you against the devil and his temptations and deceptions. Stick to God and the devil cannot touch you!

God bless!