What is the first question a reader should ask when trying to identify the themes of a novel?

There are many different questions to ask, but the one I start with is "What is a recurring moral, sentence, or stance a character takes?"

A reader should ask himself/herself:

What is the main conflict/plot in the story? How is the story presented? (The plot, setting, style, narrative techniques and devices presented throughout a story can help to identify the main theme or themes). How are the characters presented or how do they change? (Character development or character arcs can also represent the main themes).How was the life of the author? (Knowing the author's biography can help to understand his/her style, the character and story even further).