There are many ways you can structure governance. It's just how you decide to do stuff collectively. In certain contexts (such as in crisis) you might choose to follow orders from one person, for example the lead firefighter. Generally for decisions which are not time-critical simple majority is pretty poor and often leads to polarised and ineffective decisions.
Anarchists tend to favour consensus, with voting as a backup if consensus fails
Anarchic societies exist/have existed? In recent times I mean, not back when we were hunter-gatherers or something.
All societies have some anarchism in them, they can't function without it. Think community programs like buy nothing, classes, repair sheds, disaster relief efforts etc. Some societies have been more anarchic than others, David Graeber and David Wengrow cover some of how authority and power have been handled in their book The Dawn of Everything, mostly in the Americas where large and less heirarchical nations existed before colonisation (and some super hierarchical ones too). It would be a good jumping off point for finding more research via the citations.