The world does not have enough room (arable land and capacity for social organization) for 7.6 billion humans to become self-sufficient homesteaders. Civilization has long broken the nitrogen cycle and currently about 70% of human muscle protein already needs to be sourced from fossil fuels (comes from natgas---one can measure this) which are finite rather than the sustainable cycle that involves recycling nutrients rather than the practice of flushing them into the sewer using potable water.
So that's the global predicament ... locally though, some countries (particularly rich, developed ones) use food calories rather inefficiently by cycling them through animals for meat and milk. Note that we're sofar okay with doing this even if other people far away become malnutritioned because they're 20x+ poorer than we are and thus can't compete with richer people, like us, who buy grain to feed chickens and cows so we can enjoy a good burger. (Note how the oil price didn't go to infinity in 2008 .. rather, developed nations gave up more frivolous behaviors which reduced demand ... because there's only so much Joe Average Consumer can afford. This, then, put a cap on the max oil price. Similarly, in 2012 when there was a water shortage, lots of cattle were killed .. beef, ironically, became quite cheap.)
These days, concern for other humans seem to stop at the national borders as nationality makes for a handy team-marker when it comes to us vs them. I'm not sure how far a rich developed country would go when it comes to malnutrition within their own borders. Most have methods to avoid that such as WIC and SNAP in the US (food stamps) or similar. For more widespread shortages, there's a [war-time] tradition for rationing. In that case, having your own garden/homestead would certainly make you better off... As long as it stays yours; because you might be expected to share either voluntarily or forcibly.
Before it comes to that, expect wide price swings from time to time. And being priced out ... imagine your grocery budget going from 20% to 80% or 120% for a year or three. Can you handle that? With ERE you can. Other people tend to riot instead (see tortilla crisis).
Lloyds (IIRC) expect global famines to occur a few times over the next century. One year is doable. Two or three years in a row is when civilization breaks down. Historically, people have eaten their pets (dogs apparently make for a "dainty dish" whatever that means) and if that didn't do it, sold their more valuable progeny while eating their less valuable ones. Desperate people do desperate things. Dealing with this goes way beyond growing a few tomato plants in your backyard in full view of your neighbors. Even if it's a start, it's nowhere near the finish line. Then again, I think Prosper was meant as a practical beginners book for people who pay attention.
For starters, I suggest doing something like this
viewtopic.php?p=135933#p135933 and leave the gardening to people who are into it, for now. Having a backyard garden that will supply a few weeks of vegetables might feel good, but it's not nearly as effective in dealing with price volatility, which will be your first problem, as keeping a food buffer (3-24 months) and having savings.
