Can I just direct you to the scripture “Psalm 103:12
As far as the east is from the west, so far hath he removed our transgressions from us.”
When Jesus died on the cross the last thing he uttered was “It is finished.” What is finished? The sacrifice once and for all. When Jesus died He became the sacrifice and took ALL our sins to the grave and then rose again on the third day glorious! All He asks from us is that we enter into a relationship with Him and accept His death (where He took our sins away) and His new life (where we are made righteous). When we are born again, which is accepting His death and life we are born into His new life and our sins in the past, present and the future are forgiven. This is called ‘grace’. This is the reason Christ died so He could take our sins away and clothe us with His righteousness so that when the Father looks on us, He actually sees Christ, glorious and resurrected. There is no need to ‘think back’ and remember all our sins to confess. We can go to God now, in our car, or at the park or in our study and just pray and ask God to forgive us for any sin we have committed and He will forgive us. He says so in 1 JOHN 2:12 “I write to you, little children, because your sins are forgiven you for His name’s sake” Your sins are in fact already forgiven. They have been since Christ died. All we have to do is accept that and live by faith. “The just shall live by faith”