When Jesus die upon the cross how many of you sins were in the future?
Your comment: “When Jesus die upon the cross how many of you sins were in the future?”
Baptism was given to take away the sin inherited from Adam (original sin) and any sins we personally committed before baptism—sins we personally commit are called actual sins, because they come from our own acts.
For sins committed after baptism, a different sacrament is needed. Confession. Since he would not always be with the Church visibly, Christ gave this power to other men so the Church, which is the continuation of his presence throughout time (Matt. 28:20), would be able to offer forgiveness to future generations. He gave his power to the apostles, and it was a power that could be passed on to their successors and agents, since the apostles wouldn’t always be on earth either, but people would still be sinning.