Do you think God wants you to become a better person? Yes, of course He does - and the reason is because He loves you, and He does not want you to go through life the way you have been, and end up destroying yourself.
And this is why the first prayer you need to make is a prayer of confession and faith - confessing your sins to God and by faith asking Jesus Christ to come into your life as your Savior and Lord. You can't change your life by yourself; you aren't strong enough. Instead you need God's help - and He wants to give it to you. But before He can help you, you must open your heart and life to Christ. Why not give your life to Him today?
Then ask God to strengthen your faith every day. Some people accept Christ into their lives - but then don't do anything to strengthen their faith. Jesus compared them to tender plants that begin to grow, "but they have no root. They believe for a while, but in the time of testing they fall away" (Luke 8:13). Don't let this happen to you!
Instead, get in a church where Christ is preached, and where you can learn from the Bible and from other believers. Make the Bible part of your daily life also, and pray about every situation and temptation you face. Just as we need food to grow strong physically, so we need the spiritual "food" of prayer, the Bible and fellowship with other believers to grow strong in our faith.