Salvation is a free gift of God (Rom. 6:23). Jesus bore sin in his body (1 Pet. 2:24), and paid the penalty for breaking the Law of God, which is spiritual death (eternal separation from God, Isaiah 59:2). If you want salvation, you need to admit that you are a sinner and that you want Jesus to forgive you of your sins. You must acknowledge that there is nothing you can do to earn forgiveness and that Jesus is the only way for you to be saved (John 14:6). You must turn from your sins (Acts 3:19). Pray and ask Jesus to forgive you. You need to trust in him completely. Seek him; he will save you.
Repentance is part of salvation. Once saved, you should stop doing those things that are displeasing to God. He will live in you and give you the ability and desire to resist sin (1 Cor. 10:13). When you are saved, expect to change -- for the better.