I don't have any property, but have been educating myself on how to cultivate my own fruits and vegetables. I never realized how simple and easy it was to just grow food, and assuming that you're not doing it on a mass scale (fields upon fields) it wouldn't take any more than a couple of hours per day of babysitting in order to reliably produce enough food to keep you going. Protein would be an issue, since animals take up so much space, but my family used to raise chickens so - even though I absolutely despise them - I can do that for eggs. Finally, every single red-blooded man on Earth should know how to hunt for his food, and not only that, how to hunt safely and sustainably, without obliterating either his food or his food's ecosystem. I was lucky to have a dad who thought this was important, but if you didn't, get a rifle and a hunting license post haste so you can practice.