SOLVED. Fantasy Book - Boy becoming a mage (also a warrior) his uncle is evil ruler and he and his father fled. Sells his sword to buy a wand.

[Christiaan]

Fantasy / Maybe Young Adult

a couple years ago I read book series where I cant remember the excact character names or book name.

Details:
it starts with a boy and his father living in a country that is traditionally the enemy of their homeland that is ruled by the boy's uncle who banished the, _> their surname was really important as it connected them to their uncle

The boy is supposed to try and enter a school for sword fighting however he prefered to become a mage and he sells his sword to end up buying a wand. He goes to the try out as has to do some test where had to send mage bolt or fire bolt and so he collects the energy needed (different types of energy for different uses in magic) and causes some kind of miny explosion which hurt him and he gets helped by girl who heals him who is related to the king

other important factors. the boy learns at some point how to make some kind of portals. There is also somekind of girl who becomes the enemy at some point but she is communicating with her mother in some spirit realm. His father becomes a general.

I hope you are able to help me find the name of this book

[Christiaan]

are much searching I found it myself :P -> Kin of Kings