Another jobs!!!

[ArqdaniPR]

I'm confused, I want to know if I can be a white mage and a black mage. Thats possible?

[Arriverderci]

Yes.
You can be all classes into one character.
Must be level 30 Conjurer and 15 Arcanist for White Mage.
30 Thamhoneyhamturgey and I think 15 Archer for Black Mage

[Enkidoh]

Yes you can be a White Mage (WHM) or Black Mage (BLM) - these are Jobs, which are special upgrades to the class you start as.

As Arriverderci said, you have to have two specific classes for each Job at certain levels, plus on top of that, you need to do all the quests available for that class's guild up to level 30, after which you can then unlock the job by completing a special Job quest.

This rewards you with that Job's 'soul crystal', an item which is equipped like a weapon or piece of armour, and that changes your class to that Job.

Hopefully that wasn't too difficult for you.