Lemme see.... Fireball practice.... That's either an "indestructible" target or a wall done for....
Although this one seems to take things a tad slower than "OP from birth".
Book? I hope he's talking about his grandpa's book, or a book he got from a travelling magician or something along those lines, and not a magical book that will insta teach you spells - I'm so sick of these MC's that are just handed everything without any actual effort.
It's pretty clear MC got his hands on a "normal" book and got to his current power on his own effort.
Mind... he's obviously a prodigy, and isn't
supposed to be able to do the things he does at his age, but no-one's told him that. Certainly not his parents, who may not be slouches in their own right...
He's simply already studied most of the curriculum up to second , possibly even third year.
Which makes the attack with the fireball double-damning, because first-years ordinarily
can't defend against a fireball, so that was an attack meant to kill, or at least injure...