I think what you desire is quite common in people who have just overcome addictions, I have heard this very specific idea (wanting to become an addictions counselor) many times. I even had my version a couple years ago, not addiction counseling per se but I was interested in training to become a psychotherapist part-time (I am already in the mental health field so it would not have even been a long shot). I am glad that I eventually did not go for it though - I don't think I would be very suitable for that type of work and getting there is a huge investment in terms of time, money, energy, etc. I don't even think that I would enjoy the work as much as I thought back then.
I think it is a good idea to explore the area as a volunteer first before making any more solid decision. I would investigate in more depth the practical aspects: what that work involves exactly, what kind of training would be necessary, how long, costs, and what sorts of work opportunities you could have eventually with official certificate/license where you are or would like to be. I think a year of causally exploring is a pretty good time frame. Also, in terms of working with addicts and recovering addicts, you can also do some here on SR, in one of the face-to-face peer support programs, and there are likely volunteering opportunities at rehab centers, shelters, even public educational programs if you are into that sort of thing. I would say definitely try it first for a while to see from experience and to see what is realistic for you.