TwoSix
Everyone's literal second-favorite poster
"How does the calendar work, so I can define my character's birthday in my background" is a worldbuilding question.Well, in my game all the above is 'Background' and is something that the player would create and write up before the game.
I mean, it seems like your game would be divided into 2 phases. First, there's one-on-one sessions with players where they ask questions or read notes to establish as much background information as possible. Second, there's actual play at the table.