If you are asked to discuss imagery, this means you need to discuss the figures of speech in the poem (similes, personification, metaphors, onomatopoeia, etc.) Imagery refers to the words/ideas in the poem that create vivid images in our minds and these are generally created through figures of speech.
Hey I really loved the video and I even subscribed for more videos... but could you also make the video for the poem "somewhere i have never traveled, gladly beyond bye.e Cummings"