The Trials of Apollo, Book One: The Hidden Oracle by Rick Riordan

Angry at his son, Zeus banishes Apollo to Earth as a powerless, average teenager, leaving him to fend for himself in modern-day New York City. Surrounded by immortal and mortal enemies, Apollo must learn what it means to be human in order to find a way back to Olympus. And so begins Riordan’s Percy Jackson spin-off series. Apollo is a self-centered and egotistical god despite being trapped in the body of a boy named Lester Papadopoulos who he describes as flabby and riddled with acne, which provides laugh-out-loud moments as the formerly handsome god struggles to understand humankind. Trials of Apollo, like all Riordan novels, is a page-turning epic adventure, but this time told from the point of view of an arrogant god. There are multiple cameos from characters in the Percy Jackson universe, including Percy himself, but Apollo is the main attraction as the arrogant narcissist who grows into a charming hero on a perilous journey of self-awareness.