Beah’s narrative follows a common trajectory in narratives about war: he discusses how he moves from a state of innocence to one of experience. At the beginning he is living a normal life, which is suddenly and forever destroyed when the civil war comes to his area of Sierra Leone. What is Beah’s life like at the beginning?
The original question had to be edited. I think that Beah's life in the exposition of the memoir is steeped in this idea of innocence. The fact that he seems to be a "regular" adolescent helps to enhance this state of being. He likes rap music and enjoys hanging out with his friends. The Sugar Hill Gang helps to provide the soundtrack of this state of innocence. His friends are important to him. Beah has no concept of the political setting around him, and is not directly impacted by the Civil War. His foray into this realm is when he and his friends are on their way to a talent show.
The life Beah leads at the start of the narrative is one that reflects what childhood is and what it should be. This state of innocence becomes a stark contrast to the condition of being on the run for his own survival and then becoming a child soldier, a killer at the youngest of ages. For Beah, all of this has a starting point. The life he led as a child at the outset of the work becomes the point of reference for how much his life changes over the course of the narrative. It allows the reader to understand how much his life, and the lives of so many child soldiers, deviated from what was into what happened.