In every case, though, the meaningful help has come from someone who knows me - either because we talked shop at the gym, played football or board games together, or because they were actually formally my manager (or CEO or whatever). So I think it's unlikely anyone could _really_ help you online with this particular problem.
In attempting to replicate my mentorship experience for someone else, I find that this is easier with some people and harder with others. I haven't yet quite captured what it is, but I think at least a small portion of it is the will to progress in an exploratory manner and iterate rapidly on that. i.e. you don't actually find out what you want to do so much as you aim for a safe but challenging opportunity in some area that has clear success criteria and then you see if that specific opportunity thrilled you.