God will forgive you through the gospel of Christ. Your sin debt is paid in full, through His blood, the forgiveness of sins, according to the riches of His grace (Ephesians 1:7). The gospel of grace is Christ crucified for your sins and risen from the dead (1 Corinthians 15:1-4). Grace is what Christ did for you at the cross. His resurrection is assurance that your sins are taken away.
God will forgive you at the cross of Christ. You are not forgiven of some sins. It's far better than that. You are forgiven of all sins. The blood of Jesus Christ His Son cleanses us from all sin (1 John 1:7). When you believe on the Lord Jesus Christ, you receive the forgiveness of all sins.
God will forgive you through the confession of sin. Christians are not perfect, just forgiven (1 John 1:8-10). When you sin, confess your sins to God. Fresh cleansing is available. The promise of God is sure. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness (1 John 1:9).
God will forgive you to the praise of the glory of His grace (Ephesians 1:6). If you have any doubt about God's willingness to forgive you, look at the cross of Jesus. "Mercy there was great and grace was free." Because of God's mercy and grace in Christ, your sins are forgiven.