HolyJoker
Loving this, excited to see how this is gonna play out since I don't think he'll be able to reach the level of yami and the others since song of ice and fire doesn't have power levels to the extent, atleast as far as I know so this might just end in this world. Regardless I'm excited to see where this is gonna go, rare to see a good got/asoiaf fanfic that isn't just blatant romance self inserting.
Will he learn other types of magic? Glamour magic of Melisandre is hella useful. Not to mention, the fire magic. Also other types of magic like spellsingers, stormsingers, and aeromancy that are mentioned in Canon but not elaborated upon. That will provide you with a lot of creative liberty to work with. Also blacksmithing seems to be a very useful skill in got.... Maybe he can find a way to infuse steel with dragon glass and create a type of steel that can kill white walkers....