explain how narrative viewpoint and structural choices such as plot and characterisation advance the author’s position on the issue

This is really a detailed question for this short-answer space. Scout is the narrator. In the story she is looking back as an adult to the two years of her life when she learned about courage and kindness and the importance of doing what is right. The first-person perspective of Scout's narrative voice of both child and adult is a unique perspective that plays an important role in the work's meaning.