My organising and planning ability is atrocious . With cooking I am very much a chuck it all into a casserole dish, frying pan or saucepan person. Too many ingredients to deal with and instructions and I get flustered. A lot of recipes you get online or in books just seem too complicated for me.
I wasn’t sure whether to put this here or in lounge, but plumped for here as it’s an activity of daily living. Many of us have problems with one or more ADLs .
@firemonkey
One good idea is to buy a slow cooker.
You can get chicken breast for example, freeze it. And then one day defrost it, chop it up, add it in the slow cooker + some frozen vegetables and a ready made powder seasoning and just let it cook.
Just do easy recipes. These ready made sauce and powder sachet are so cheap and easy! I am using that when I have to cook everyday. Like general tao, peanut butter sauce, teriyaki, mushroom, etc.
Is that really a sauce name?! 
Lol yeah it is a very popular Asian dish name. It is very good.
I have a small and large slow cooker. Your suggestion sounds good. I like the frozen veg idea that’s ideal for a person like me who struggles with chopping and peeling veg. The drawback is potatoes I struggle to peel and chop them. Usually for casseroles in the oven I chuck in tinned potatoes but you don’t get that many potatoes per tin.
Also using a ready made powder seasoning makes some sense although I am not sure how many packets one would have to use.
Does the liquid have to cover the ingredients? I tend to find when I do anything the gravy is thin and watery. I prefer mine fairly thick.
The way I plan my meals is to keep in mind their price at the store, their nutritional content, their taste, and the difficulty in preparing them. I get a lot of my meals from the freezer at the Dollar Tree, which means I eat a lot of processed meat. Some people think that’s unhealthy, but I get a lot of protein. My food stamps have been cut by over half, so lately I have been asking for the leftovers at the clubhouse after lunch. It’s not too difficult for me to average a cost of less than a dollar a meal. I bought a big bag of brown rice and several cans of black beans to fall back on when nothing seems appealing to me. I season them with butter and salt, and though that might give me a heart attack, it makes them taste better. Also, there are those boxes of macaroni and cheese that make a good meal for substantially less than a dollar.
I buy a mix of vegetable. Broccoli with carrots. Peas and beans etc. and just wash them them throw a cup in the cooker.
Buy frozen potato wedges and microwave them if you fancy some potatoes. Or buy a whole one, wash it, cut it in half and microwave cook it on high heat. Just check your microwave’s instructions please so it does not burn.
I use one sachet of powder for one steak with mushrooms for example. Or for one chicken breast with vegetables. I think one chicken breast is good enough for someone like you? along with vegetables? so one sachet is good!
Please check your slow cooker’s instruction manual or just google if you can not read a lot. Usually I add one or half cup of water, just enough to submerge the ingredients inside. What I do is, mix the sauce with a 0,75 cup of water and just drizzle on top and then set the time.
This sounds like foreign language to me. I must be the world’s most incompetent cook. 
I’m able to follow recipes but my body would rather starve than do it everyday.