The Savior gave His life for us and suffered for our sins. This great sacrifice is called the Atonement. Through the Atonement, you can receive forgiveness and be cleansed from your sins when you repent. When you do what is necessary to receive forgiveness, you will know for yourself the power of the Atonement and the love God has for you. You will feel the peace of the Lord Jesus Christ, which will bring you great strength.
Satan wants you to think that you cannot repent, but that is absolutely not true. The Savior has promised you forgiveness if you will do what is required. The sooner you repent, the sooner you will find the blessings that come from forgiveness.
Some people knowingly break God’s commandments, expecting to repent before they go to the temple or serve a mission. Such deliberate sin mocks the Savior’s Atonement and invites Satan to influence your life. Repentance for such behavior is difficult and can take a long time. If you sin in this way, you may lose years of blessings and spiritual guidance. You may become trapped in the sinful behavior, making it difficult to find your way back.
You always need to confess your sins to the Lord. You should also confess your sins to those you have wronged. If you have committed serious sins, such as immorality, you need to confess them to your bishop.