God exists in eternity. He’s bigger than time.
Think about holding a film strip. You can look at the last scene any time you want. You’re not bound by the playing time of th emovie, because you exist outside the experience.
Same with God. Jesus took every sin of the whole world from the beginning of time to the end, whether they were committed by a saved person or not.
He has reconciled the whole world to God.
So yes, every sin you will ever commit are included in your salvation. Sleep well.
My Catholic understanding of the situation:
Christ effected Redemption on the Cross by offering Himself a complete, perfect sacrificial oblation for the sins of the whole world.
He therefore becomes the Way through Whom we come to the Father, ourselves imperfect and sinful, yet we are accounted righteous (justified) in the Father’s eyes by the grace of His Son’s blood. Thus, justification in the imputation of righteousness to those who are not yet righteous but who then pledge to co-operate in being made righteous by the power of the Holy Spirit dwelling within them.
The final destiny of those who have proclaimed faith in Christ Jesus and who then work our their growth in righteousness in fear and trembling, whether in this life or in the next (usually both) is salvation and eternal fellowship with the saints in the presence of God.
Thus, redemption => justification => salvation
True. In the sense you say, Christ died for every sin that was ever, or will ever be committed. All is covered by His ultimate sacrifice, but He does require us to come to him in repentance and faith in order to receive what has already been atoned for.