you can still grow herbs and such in pots and window boxes... learn about the trees and other vegetation growing in and around the city. Learn what food resources are within traveling distance from your home.
Before the advent of modernization, most people grew at least some of their own foods and fully 50%+ were farmers/herders of some kind.
Many traveled far (many days and sometimes weeks/months) for food and spices...
I do not foresee it coming to that for most as they will continue to pay for the worthless fodder in the stores. For others...