Most people, like you, who can afford to be on the internet are probably well fed and are able to eat things you don't really need to survive. In a The End Of the World As We Know It (TEOTAWKI), situation, this could be a disadvantage. As soon as you know you can't have something that you like to eat, you are likely to start craving it. This can be very hard to deal with. Americans often do this when they travel outside the USA.
I enjoy asking people what they miss eating. The most common American answer is hamburgers. Ice cream is usually next and then ethnic fast food from their part of the USA. I think Mexican Food is the most common of those. That is what it was for me. I just thought I was dying for a spicy burrito.
I made up a saying for myself that I use to explain some things. It is, "Get more or want less." If you simplify your food and other needs now, you will miss them less when you can't have them. This will also lower chances that you will face a nuclear disaster as soon.
When you have x resources and x+ people want to use them, people are more likely to fight over them. Bearing that in mind, I have deliberately reduced the level of resources required for what I regularly eat. This means that I eat more one dish meals and I use more simple ingredients that I might be able to grow myself or get locally. I eat more food made with basic staple ingredients like beans and rice. I have also learned to make more of my own Mexican food.
"Eat local, think global", is a saying that will help you understand how to do this. When you eat food that is grown closer to you, it takes less fuel to get it to you. You are using less resources.
None of this means that you have to eat food that is not tasty or satisfying. I have learned to eat well, even though it is simpler and costs less.
You can learn cooking techniques that allow you to eat less prepared foods. I do grind my own flour some of the time, for example. That is really basic, but it also saves a lot of money. Grain is a lot cheaper than flour, and fresh ground is better nutrition and tastes better.
Making your own mixes is another way that you can eat more simply and save money as well. There are a lot of nice sites on the internet that have great recipes for making your own mixes for just about anything.
Before all of the sites with mixes were available, I bought a book about making your own mixes. It is called "Make-A-Mix", by Karine Eliason, Nevada Harward, and Madeline Westover.
You can look at the recipes you use the most and see what dry ingredients are in them. Once you do that, you can invent mixes for your favorite foods.