I can't give medical advice, I mean I can but I won't. Anyway, I was a professional chef who worked in three very different locations before leaving the pirate kitchen life of sodomy.

What's affordable is going to depend on where you are, so buy in-season fruits and vegetables. Try different recipes using things you know you can afford and when something clicks for you, write it down. Keep a list of the healthy meals and snacks that are easy for you to make because the hungry brain has no past or future. Aggressively mid foods like beans, peas, potatoes, barley and peanut butter are cheap and no one will care if you steal them.

If you're a shit cook find some videos and follow along or ask a friend to walk you through some recipes if you have one.

Keep heathy, craving satisfying food on hand. Make a batch of nut balls (nut butter mixed with seeds, dried berries and whatever) and keep them in the freezer. Have lots of different tea on hand if that's your thing, popcorn is filling and low calorie. My go-tos are: hard boiled egg, or a baked potato, or a bowl of peas. Don't knock a bowl of peas until you try it after a joint, mixed with coconut oil, salt, pepper and cayenne.

Try smoothies. One of my faves is almond milk, spinach, lime juice, cashew or hemp butter, banana, pinch of salt. Blending up greens is a great way to stuff them in and they're low calorie by volume. What's great is I can pre-portion all of those ingredients except the almond milk into containers and freeze them. Then making a smoothie is as simple as dumping the frozen brick in a blender with some liquid.

Grocery store prices can vary by day, sales usually go on before they get in a new order and need to clear the shelves. Figure that out and only buy meat in bulk on sale or wait by the dumpster at night. Make a big batch of something like curry, chili or stew with it and freeze in portions anything you won't eat in the next few days.

There is no shame in using low-income grocery options to get healthy food you can't otherwise afford. See if there are any in your area. I have friends on disability who get a box of fresh fruit and vegetables every week, food that's perfectly good but would otherwise be thrown out because of our high beauty standards for crops.