Any race can become any class. Just remember that some races that are good-only may need to do a Betrayal quest to become a class that is evil-only.
However, there are neutral races and classes for both sides. As a Wood Elf, you would begin in Qeynos as a Mage, then talk to Magister Niksel for your
Path of the Summoner quest.
Once that's done, you must then do a
Betrayal Qeynos to Freeport quest. I believe the level cap is 18 to start it. Make sure you first collect all your things from the Inn room and check out, as you will be banned from the city once you start. Also remove anything from the shared bank, as it does not share across Qeynos-Freeport.
You can find the info for Path of the Necromancer
here.
Good luck.