It is not typical of most people to plan out a week's or even, a month's meals. Three meals a day for 7 days is 21 meals. For 30 days, it's 90. Is it any wonder that many people turn to repeats of processed food meals, often microwave zapped?
The meal plan is not a recipe. It often contains single titles for meals and it serves a number of great functions, 1) Calorie Limits, 2) Food Group adherance, 3) Identifying Grocery Needs for re-stocking or acquisition and 4) elimination of redundancy (eating the same stuff too often).
In the USA, the Department of Agriculture documents and recommends the Food Groups that every American should be taking in.
Executive Summary - 2015-2020 Dietary Guidelines | health.gov
MyPlate | ChooseMyPlate
This goes for three meals per day with snacking in between meals.
And it's hard for an old grizzler like myself to deal with these guidelines as a single meal is puny by their definition. I'd be unhappy with anything, but a big meal. So, I eat a small breakfast and later in the day, one big meal, without a lot of snacking in between. I'm not a constant grazer. I eat and then expend, exerting or sleeping in between.
So, when I consider meal plans, I don't follow the Dept. of Agriculture guidelines. My choice. My habits.
Calorie management is a different matter. You need to know your gender, age and Body Mass Index. You need to know your daily static calorie burn, just sitting, doing nothing. Then you need to understand how many calories you burn in exercise or exertion and finally, calculate how many calories you can take in. If you want to loose weight, you need your calories to be less and calorie burn to be more. These days you can find out how many calories are in food, even meals you cook. It's either on the label or listed on the web.
Reviewing your meal plans can suggest eliminating things that are often repeated by exploring something new. And when you know in advance where you are going, you can plan your trips to the grocery stores, more reliably.
Before I close this post, let me say that I do not cook every day. I use a lot of time, even as an old retired guy, and often microwave prepared and processed foods or do quick meals like Macaroni and Cheese (for example) or tuna salad sandwiches, etc.
These days, with the pandemic, restaurant food has been almost totally eliminated from consideration, leaving a lot more to be done for food and meals, at home.