I personally know some folks who spend all their money on fast food, and then online it seems pretty common folks not knowing how to cook causes massive financial problems.
My super duper cheap meal that takes no effort is “lazy rice veggie soup”: Can of peas and carrots cooked with a bouyon cube until cube is dissolved Add cooked rice to mix, and heat until rice is flavorful with absorbed broth
I do a cup of dried rice, and a can of peas and carrots which means the soup has 800ish calories and I think it’s pretty good as it’s either 2 small meals that you can have sides with, or one large one!
So what are your cheap meals you like to make? The less well known, the better!
Ghetto pizzas. Make some toast put tomato sauce or ketchup on it then sprinkle with cheese. You can nuke it to melt the cheese or if you want to spend more effort pop it in the oven. Also if you have more than 2$ you can put toppings like veggies and pepperoni on it.
Edit I just remembered another poorman meal I used to eat all the time. Boil ramen and strain. Add tomato sauce and cheddar. It’s like really shitty spaghettios or regrettios if you will. Cheap filling and full of sodium
You can do this same recipe with the great big burrito tortillas, too.
You can make “Toast Hawaii” the same way: Slice of toast, put ham on it, a ring (or pieces) of pineapple on top, cover with a slice of cheese, pop it in the microwave for a minute or two until the cheese has melted. One of the rare “non traditional” meals my grandma used to love, and super easy to make.