The Question and Answer section for The Martian is a great resource to ask questions, find answers, and discuss the novel.
I'm not sure about what the exact process was called, but Watney distills water from the air and uses biological material (human waste) to provide the soil with nutrients.
they pressed the button
For the most part, Watney responds logically (scientifically) rather than emotionally. He realizes that in order to survive, he will need to create his own food supply.