We would advise you to look at the plan a little more flexibly. When the plan suggests you eat similar foods that go bad quickly, you can use them interchangeably during the week. This goes for meat like chicken, turkey, or other – simply use the type of meat you have. The same applies to bread.
Sauces usually have similar caloric values, so you can switch them to the ones you have and enjoy your meal nonetheless. Just keep an eye out for hidden sugars and choose products with less fat in them. This also applies to spices and similar condiments.
Products like legumes, seeds, rice, or nut butter don't go bad fast, so you can buy them in larger quantities. You can also buy larger amounts of frozen vegetables, fruits, or meat. It is an effective food preservation method: you can use even the smallest amounts without the fear of leftovers going bad.
Opt for budget-friendly ingredients such as canned legumes, seasonal fruits and vegetables or frozen produce. Shop sales and discounts for products that are still safe to use.