Complex sentence: When Copperfield was 10, he began practicing magic as "Davino the Boy Magician" in his neighborhood, and at the age of 12, became the youngest person ever admitted to the Society of American Magicians.
Split into simpler sentences: When Copperfield was 10, he began practicing magic as "Davino the Boy Magician" in his neighborhood. D and at the age of 12, became the youngest person ever admitted to the Society of American Magicians.