I will assume
Assuming that we are talking boats here, and not around the house. When out on the water my usual start for the day is first coffee, at least two cups. Breakfast is most of the time instant oatmeal, which when out for a while is great because it requires not much space and no refrigeration. To keep from becoming too much in a rut, I also keep pancake mix, and enough bacon and eggs for a few meals. And of course some orange juice. Mid day meals usually are just snacks, cold cuts, crackers, etc. For an evening meal it varies greatly, but usually eat pretty good, and fresh fish is preferred when ever I manage to catch one.