Basically they are not expecting your child to come up with some new idea about a 200 year old poem. Start with Mr Bruff, he will spoonfeed the information to both you and your son, in a good way. I have an English lit degree so I love all of this to some extent, both my Dh (engineering degree) and my teenage sons are STEM lovers.
Ds1 learned that you are just repeating/regurgitating what someone else says about the poem, plenty of information online including what that massive list of literary devices mean, all in video form from Mr Bruff, he is at a really accessible level. You are to support your son, not teach him. He will have used some of those literary devices in primary school especially a simile! He has a teacher in class who will explain stuff to him. This is how people feel about maths by the way
they don't understand it, it is easy for you, hard for others.
As you are looking at poems written around mid 1800s why not watch some films of the same era to see it visually rather than trying to explain. A great one would be Pride and Prejudice which will cover women's prospects - to marry well, sex outside of marriage with Lydia and the shame that brings not only to her but the rest of her sisters. You see the dances, balls make or break connections due to behaviour, the manners, the bowing, the posh ball and the local ball with everyone there. You can pause the film and chat about it, see how they are introduced in age order from oldest to youngest, when you get married the order changes to the married woman first!
Neither of my sons was/is interested in the poems and they were doing the Power and Conflict ones about war mainly! The more marks you can get on just knowing what to write about the poems you are taught, the better as the most marks are for the unseen poem and that was incredibly hard for Ds. He doesn't understand nuance or suggestion in a poem either.