I think a lot of permaculture-specific theory in books is either stuff that seems
common sense (e.g., keep the highest-maintenance stuff close to home, don't kill your soil) or stuff that seems really complex, especially if you can't pair that theory with practical knowledge. (I always remember theory a lot better if I can try it out and go, oh okay,
that's why.) I know you're in a small space but I would be tempted to identify specific permaculture skills/techniques that you can practice in the
city and focus on those for now. Even with a patio garden you can learn a lot about growing plants and you can save your own seed etc. You can also learn foraging; if you know how to identify, collect and use wild plants or "weeds", those plants can be a very useful part of a permaculture design (
fallingfruit.org is great for urban foraging and
Seek is great for plant ID). Guerilla
gardening is fun and can be as easy as making seed bombs or as advanced as
guerilla grafting.