Rice and beans is the staple pretty much everywhere else.

Don't buy ultra processed Mac and cheese or frozen pizza. It's nutritionally bad for you, and won't keep you full for long.

Start with rice and beans and canned sauce. Cheap, easy, and good for you.

You can obviously add chicken/tofu/protein, or try to start making sauces yourself. But always keep the rice and beans as a base. Every meal you eat, rice and beans. They're cheap as hell and close to what we evolved to eat.