How is death presented in the poem

“Dulce et Decorum est” is an angry statement against those who see glory in the death of soldiers in battle. The title of Wilfred Owen’s poem is referring to the common saying during World War I, “It is sweet and fitting to die for one’s country,” which Owen saw as political propaganda for the recruitment of young soldiers.
Death is pervasive in the poem, following the soldiers as they march back to camp from the battleground, “blood shod,” with the red blood of comrades, enemies, and themselves. Ironically, one man is so exhausted from the battle, he is unable to react in time to a gas shell shot at them from the distant battle. The description of his slow, torturous death from inhaling the chlorine gas is harsh and haunting. Owen sees him “Floundering like a man in fire...guttering, choking, drowning.” He tells the world, “If you could hear...the blood / Come gargling from the froth-corrupted lungs,” you would not tell children, who are desperate to believe that adults are making the right decisions, “The old Lie: Dulce et decorum est / Pro patria mori" (It is sweet and fitting to die for one's country).
https://www.poetryfoundation.org/poems/46560/dulce-et-decorum-est