The Wizard Who Cannot Be Defeated

My uncle and aunt told me that I couldn't become a wizard. When others had received their admission letters to the Academy of Magic, I still had nothing. I was destined to become a mortal. But at this moment, an old wizard appeared in the relics left by my parents. He was the most evil dark wizard two hundred years ago. He was defeated in the Second Wizarding World War. However, now his soul has been fragmented into countless pieces. If I help him resurrect, he guarantees that after he regains control of the wizard world, he will make me the president of the Magic Association and also let me become the president of the United States. -- All of the above are false. Actually, I'm just a pitiful person who had my magic sucked dry by an evil dark wizard. I have to bring the dark wizard along to study at the Academy of Magic, and I can't let anyone find out.