Are you looking for an affinity group as described in the linked text or in general participation in anarchist projects in groups?
I think for the first its really hard if you currently dont have many personal connections to like minded folks, but the second one is something I really encourage you to try out.
Also if consensus driven / non hierarchical activism is your main focus, you might find groups that are not anarchist but (try to) practice their activism this way. Its kinda the current way most groups aspire to organize themselves if they are not specifically hierarchical.
Edit: also while the foodnotbombs group might currently be inactive, you could still try to shoot them a message via social media or email and ask them for connections and ideas in your area.