In the opening scene, why does Paul's company have extra food to eat? Why is Franz Kemmerich dying? How are Muller's feelings about Kemmerich's dying different from Paul's feelings?

The cook, Ginger, has prepared enough food for 150 men, but after the last day of fighting only 80 men remained in their ranks.

Kemmerich had his leg amputated after being wounded in battle. He will die from his injuries.

Paul worries about having to give the news of his close friend's death to his mother (Kemmerich's mother). Muller simply wants Kemmerich's boots ecause he'll no longer have need of them.