1: You running out of food is kind of weird. A MRE arrives at the base in a box in the garage each day. Usually keeps you full for a long time.
2: There's hidden burgers inside and outside of the base. It's mostly a collectible advancement, but the burgers are still food so-
3: There's mushrooms around the base walls if you run out of food. They aren't really nutritious, but they regen. Use em to get a little bit of a boost to get actual food.