Hi nightshift. I am a convert to the Church and I also had to give up some vices to get baptized. All I can tell you is to follow your heart and do what you know is right.
Giving up coffee and chewing tobacco can be very very tough. I know because I gave them up!
I must tell you that after my baptism I slipped up and went back to my old habits. The Word of Wisdom has always been a strugle for me.
If you decide to goin the Church, which I pray that you will, make a commit NOW to stop all of those horrible vices. It will make it easier when you do get baptized to not go back to them like I did.