Is it possible for one to become a fire wizard?

On the anime Avatar it is possible to become a Fire Bender - which is virtually the same as a fire wizard.

In real life: there is no evidence that magic of any type actually works, so while you can call yourself a "fire wizard" if you like... there's no State Board of Fire Wizardry to insist that you pass a practical examination first... no, it's not really possible.