Don’t worry! One of the benefits of a mooc is there is no clear or “true” one right way to engage in them. Some people read, some write, some talk, some don’t — do what works for you and meets your needs.
Of course, having some presence where you share it back with the community will ultimately strengthen and grow it, in turn helping others who are also struggling to navigate it. BTW, there is not a single roadmap of where or how to start . . . in this way it is like Twitter . . . just dive in mid-stream!