DH is a chef so definitely can cook, but very rarely does because he’s at work all the time. Over 20 years of doing all the shopping and all the meal planning and all the cooking - it’s tedious, I get it. I’ve also had periods of fussy eaters and an allergy. I’m practically through it now as they are growing up and sorting themselves out much more. Tbh, you sound like you have more money than me so that is in your favour.
These are my tips.
Not every meal has to be a cooked from scratch delight for the taste buds. A supermarket pizza and salad is fine. Beans on toast is fine. Chicken and salad wraps are fine. Burgers are fine. Garlic mushrooms and shop bought ciabatta are fine. I probably have 10 pasta dishes in my head I can do in under 20 mins.
Use one of your days off to make something that takes longer - a slow cooked something or a bolognese or dahl. Make 2-3 portions so one can be eaten in one of your work days.
Don’t worry about every meal being crammed with vegetables and nutrition - if it’s a decent diet over a week then you’re winning.
Meal plan. It doesn’t have to be ambitious. You don’t need to introduce new meals every week (or ever). You don’t need a different thing every night (did you growing up? I didn’t.) I do one oily fish and one non oily fish thing a week so I put those down on my planner first. Depending on what they are and what days I’m working I pick good days to have those. My working days I put down something easy (batch cooked meal, easy pasta, something like burgers or wraps that are “assembled” rather than cooked). On the other days I do what I like - I might want to try something new and complicated - I might want to stick to what I know is easy and will be eaten.
Breakfast - don’t go out and buy strawberries ffs. If there aren’t any strawberries then do without. I moved from porridge to eggs for breakfast when dc1 started secondary school and was getting hungry (longer days - earlier school bus). They have 2 eggs in a wholemeal wrap - sometimes with cheese and/or ham and a recent addition (from thread on here) - refried beans. The other breakfast food available is a basic granola to which I add 2 extra bags of nuts and 2 bags of seeds - admittedly it’s quite calorific but it doesn’t half fill you up and it’s mainly good stuff. It would be a perfect easy lunch for your DH (I usually dollop in a spoon of Greek yoghurt - it’s something you can grab in less time than it takes to have a wee or order a JustEat).
Snacks - fruit. Im not a big fruit eater but I do snack on pickles. Don’t buy biscuits, cake, crisps etc.
Lunch - keep it basic and shop bought. You just want your dc to have enough to eat so they aren’t hungry during afternoon school. That’s all. Some protein, some carbs, some fruit and veg.
Your DH is an arsehole ordering McDonald’s when it’s his “turn”. KFC ran an advert a few years ago “mums night off” when an absolute bellend brought a bucket of chicken home to his family instead of cooking a meal. Imo if someone is cooking upwards of 6 out of 7 meals then takeaway night should land on one of those nights, not the 100% of nights that dad is supposed to cook. Tell him it’s fucking rude and to pack it in.
Look at your budget and see what you can outsource (car cleaning being an obvious one if you aren’t happy to have a scruffy car). Would paying a gardener help, or a cleaner? If you don’t want someone every week then a 3 month or 6 month “deep clean” is great. Getting a weekly supermarket delivery instead of having to go. Getting a Gusto or Hello Fresh for a few of the meals?