Honestly, it's very difficult to imagine and while there is plenty of literature on the subject I don't think any of us can truly say. I personally have not read the literature and for me to speculate on it would do more harm than good I think. The reality of a stateless society seems so far off from my lifetime that discussing how it might look feels like fantasizing to me. My focus has always been on getting to a point where one is possible and studying how to do so as this is far more relevant to my conditions.

Stateless societies absolutely have existed. The state had to arise at some point. Foraging and horticultural groups are examples of this but neither can sustain our current human population so no they are not practical in the way you are asking. There were also attempts at utopian communism that were internally stateless but ultimately subject to the whims of whatever state they resided in so their status as stateless is debatable. You won't find a largescale stateless society in the modern era primarily because it would make them incredibly vulnerable. Proposing, hypothetically, you eliminate class within a large industrialized society and therefore internally remove the requirement for a state, that society is still beholden to the global dynamic of imperialism. The state is still required to protect the interests of their society from the contradicting interests of capital abroad. This is why communism must be an international struggle.