How can I eat $1 dollar a day?

How is it even possible to survive on just $1 a day? I understand the concept of budgeting and saving money, but this seems incredibly challenging, if not impossible. Are there specific food items or strategies that one can adopt to make this happen? It seems like such a low amount of money would barely cover the cost of basic necessities, let alone provide a nutritionally balanced diet. Can you elaborate on how someone might go about eating on such a tight budget?