To be able to use magic, to the same extent as weapons, you'll need to have the level needed for it. The more you train one domain, the more you'll be able to ue it effectively.
The different domaines of magic are:
Fire
++Damage
Water
+ Speed (Evade)
Wind
+ Movement
+ Blocking enney
Earth
+ Damage
+ Blocking
Beast
+ Shape shifting
Nature
+Healing
+Defense
Spirit
Mind reading + telepathy
+ Speed
+Talent
Light
+Damage (Thunder)
+ Summone
Dark
+Damage (Poison - Death)
+Summone
(N.B: All elements will have damage spells, the + only surve to say which are more appreciated in that branch)