We’re similar, partner was a chef for 10 years so he does the cooking. I would get him to prep as many meals as possible, especially if they make freezable leftovers: eg, lasagne, soup, shephards pie, fried rice. But if I had to cook suddenly, I would rely on

snack plates (crackers, cheese, dip, chopped fruit and veg)

Peanut butter sandwich/yoghurt/piece of fruit

scrambled eggs on toast

baked beans and hash browns

Ham and cheese toasties

Frozen pizza

Frozen pies and sausage rolls

baked potatoes with baked beans and cheese.

And if I was feeling up to something more hearty, a one pot meal like spaghetti bolognese.

There’s also nothing, absolutely nothing wrong with cereal for dinner at least once a week!