Salvation is the work of God in Christ, not the reward for finally becoming good enough. Jesus gave His life for our sins and rose again so that we could be forgiven and brought into new life with God.
A person receives salvation by turning to Christ in faith. That means trusting Him as Savior and Lord. Repentance is part of that turning. It is a real change of heart that moves away from sin and toward God.
If you are asking where to begin, begin honestly. Tell God the truth. Believe the gospel. Call on the name of the Lord. Then keep walking with Him through Scripture, prayer, and fellowship with other believers.