It is a metaphor because it does not have like or as which means it is not a simile. There is no rhyme in it and there is also no repetition.
An author shows us what a character is like by the way they look/dress, talk, and act.
Hope this helps!
The exposition is the very beginning of the story so it should introduce the characters and the setting and maybe introduce a lesson to be learned.
It would be a comprehensive description and explanation of an idea.
