Good Morning.
I agree with you completely that the Devil is a real entity, seeking to sow death and destruction wherever possible. Too many people Christian and non-Christian alike are too willing to dismiss the Devil as being just a fairy tale or childhood nightmare. Nothing could be more reckless.
If one has come to the Saviour, Jesus Christ, has confessed their sins, has asked Christ to save them from eternal damnation, and if one is washed in the Blood of Jesus, then there is no need to fear what the Devil and his demons may do, be it at the point of death, or any time before, for it is the Blood, the Blood, and nothing but the Blood that cleanses us, washes our sins whiter than snow, and when God views us, He views us through the prism of that Blood, and we become the very Righteousness of God because of it.
God Bless You.