Your interpretation of how one who believes in god should act may be differently from yours. Just share your thoughts and concerns with your because your friend may not know that his actions bother you.
People can believe in God in their own way. Everyone doesn't believe in the same way. What you might find not good behavior he may feel it is great behavior. If he is a friend, you should be able to ask him about the things in his behavior that you are not comfortable with.
You can believe in God, but not follow his (God) word & teachings. Sounds like your friend does believe, but doesn't exactly know how to follow the word/teachings. If you go to church, which it sounds like you probably do, invite your friend to go with you. Sounds like your friend just needs to be taught that you don't go to Heaven by just believing. Your friend needs to be taught how to follow God. Only God is perfect, we all mess up & sin, but you have to ask for forgiveness & repent. Make it a weekly thing for you & your friend to go to church together (or a bible study group). It's possible that your friend wasn't brought up in a church & that he thinks that just because you believe in God you will go to Heaven. He may not know any different.
There is a big difference in believing in God and believing there is a God. A true believer will act differently, not perfectly, but differently. When the Holy Spirit enters you and becomes a part of you, the desire to sin leaves you. Maybe your friend believes only that there is a God. Stay with him and set a good example and pray for and with him.