I might add that the essays is comparative in nature (you are comparing and contrasting two poems). You can push this in any direction you wish, but I might note that Owen opts for a form in his poem “Dulce et Decorum Est” that is an alternating rhyming iambic pentameter four line stanza – this is sometimes called a heroic quatrain (this because the form was often used for ‘noble’ narratives). There is something odd about using this heroic form for the squalor of warfare I think. Owen must be using the contrast. Note too the poem feels like a report, albeit broken in tone – perhaps somewhat add odds with any lofty gesture of heroic poetry.
That much said, it is the linkage to the topic of war that should be guiding you some.
Some links that might serve you:
https://wwnorton.com/college/english/nael/20century/topic_1_05/resources.htm
This is not meant to be a research paper as such – but please cite any source material you do end up using (if you do).
https://wwnorton.com/college/english/nael/20century/topic_1_05/resources.htm