Everyone had that dream, some are lucky to achieve it, while some couldn't. I remember wanting to become an economist, but I ended in Business administration. So I just had to take it that way.
I've seen many who studied what they are not practicing. Imagine an engineer working in a bank as a banker. Even lawyers.
In this part of the world, we all go with the opportunities we have at hand. Cos when you say you will wait to practice what you studied, it's gonna take time to achieve that.
It's a wise thing when you have passion for what you want. Another thing is to take opportunities when they come. I wish you the best in your pursuit.