"We don't need and need not bother wanting to be 'independent.' Instead, we need the kinds of knowledge and skills that allow us to be valuable and contributing participants in honorable interdependence in both good times and bad." Carol Deppe, The Resilient Gardener; Food Production and Self Reliance in Uncertain Times.
While we may not be able to get specific as to the timing and exact nature of the change that's coming, we can be reasonably certain that change is on the horizon and that food insecurity will be a part of it. I would encourage you to approach this in two ways. Start playing in the garden even if "the garden" is a few pots or containers on your windowsill or the flower bed outside your apartment. Put away at least some food so that you have time to think if something happens faster than you thought it would.
As far as storing food goes, rice, beans and salt are what you need to be alive and after that you can fill in the blanks. Also, you start rationing as soon as you begin using stored food reserves. The whole point is the be here to have the option of deciding what comes next and that only requires about 1000 calories a day. Rice has about 1600 calories per pound and beans have about 750 calories per pound depending on the type. This means that 2 pounds of beans and 1 pound of rice is good for 1 person for 3 days. Figure out how many people you want to feed and for how long and you do the math. Each person you want to feed needs about 5 pounds of salt per year to remain healthy. This is the cheapest and easiest of your needs to provide. If stored salt goes solid on you, you can grind or crush it. The sodium is all you need and that hasn't changed by going solid. It is easy to get variety with spices. I encourage you to wander the aisles of the best international grocery you can find. I'm not talking about "World Market" where the rich folk shop. I'm talking about where the local Asian and Indian population shop. You will find a variety of beans, rice, grains, spices, and all manner of other cool stuff.