It's either mc stammering or having dyslexia,I really can't remember but I know he was an actor and was always made fun of because of his stammering or dyslexi
@bonny umm i don't know Auro of the genius actor and Film Emperor's Reincarnation Script, kinda match ur discription but not much... I'm just asking because I'm confused too r u sure it's manga and not novel, i search most (almost every) manga but i don't find one with same discription,