Some people believe that Jesus only earned forgiveness for some of our sins when He shed His blood on the cross, and that we need to earn the rest ourselves. But this is not what the Bible teaches. The Bible says that Jesus paid the price for all our sins:
When you were dead in your sins and in the uncircumcision of your flesh, God made you alive with Christ. He forgave us all our sins, 14 having canceled the charge of our legal indebtedness, which stood against us and condemned us; he has taken it away, nailing it to the cross. (Colossians 2:13-14 NIV emphasis mine).
Therefore there is nothing left for us to earn. The only way for God to forgive us our sins is through the blood of Christ. If you have not repented and believed then you are not saved and the blood of Jesus covers none of your sins. But if you do believe then it covers all your sins. Our basis for salvation is the Holiness of Christ, not our own inherent holiness, for we have none.