Regarding on how to avoid being deprived of strength in this chapter due to your sudden loss of food/water supply for any reason possible.
Some world religions teach us to fast during the day (from dawn till dusk as an example) to instill discipline, reduce crime & sin & to strengthen our physical, spiritual & mental health. If you learn to fast, you won't need to depend on food or drink to keep going through your days. It's not the same as simply skipping meals to comp your daily expenses or being too poor to eat, as fasting needs the initial resolve and intention to do it for your own benefits in the long run, if not for your religion. Learn how to fast intermittently or like some religion, one whole month per one year or two days per week all year round, or whenever you need or can do it. You'd even be able to go through your days without craving for things you usually can't avoid to crave for.
But if you never fasted before, don't try to do this straight out of the bat. Start with intention & resolve to finish it, & packing yourself with the most essential nutrition & hydration first thing in the morning. Then go about your day without eating or drinking anything. But if you feel faint, break the fast (with light food & water first). Next time you do it, try to do it longer. The most efficient/optimal length in a day to fast is from dawn till dusk i.e. from before the sunrise to after sundown. Good luck :)