I was thinking about how I would cope if I weren't able to rely as I do to a reliable on-line delivery service. Currently, we use a delivery service that is reliable and therefore menu planning is a part of the order process. We have virtually no waste and always have everything we need for the meal.
If I had to go out and "shop/market" I would start to keep a set of spreadsheets of my favourite meals with a shopping list for everything needed for that meal. Before I went out I would select a number of them ie the number fo days I was shopping for plus a reserve or two. I'd check to see what wasn't needed ie already in stock and then use the list to shop. Each meal might have an essential fresh essential item or two that I'd need to check first. So for example the meal might be dependent on fresh salmon being both avaialbe and good. If that was available I'd buy everything else needed ror that meal. If one of them was missing I'd go to a reserve meal.
This sounds boring but it would be my approach. The list is also good for ensuring to improve and record your repetoire.