Grand Master Schule:
Anyone wishing to become an Elven Knight must have achieved at least level 20 and passed the appropriate test.
You've accomplished neither one! Achieve at least level 20, and then speak with Master Sorius in Gludin Village. You'll find him in the Warrior Guild. Pass his test and bring me the Elven Knight Brooch as proof. Only then will I promote you to Elven Knight.