I have several cases of freeze dried food and it doesn't take up too much space, last a long time, and actually is a lot of food once prepared. Of course you have to have plenty of water to prepare it with. And it isn't bad either when compared to other prepared foods you can buy; I actually think some of them taste pretty good.
I also have plenty of regular canned goods and other non perishables. These will keep you for the first few weeks-months (or even years tbh) anyway if you have enough, which will be enough for most of the disaster events you encounter.
In a true SHTF event you will never be able to stockpile enough to live the rest of your life unless you don't plan to live very long. This is where knowledge really starts to come in as more important than stuff in prepping. There's lots of good information here that you can use to get started and then practice skills even if they don't seem immediately useful.