I’m new to this game as well, but I’m learning to navigate Medium by reading some of the publishing advice articles on THE ORANGE JOURNAL. This won’t answer all of your specific questions but she’s pretty transparent about the publication process in general. Offering formatting and other advice. I’m navigating without an instruction manual as well but turning over new stones almost every day. This is a helpful ask. Learning even more. It’s part of the learning curve here. Currently I’m writing for MODERN WOMEN. Cheers!