Few questions about custom minigames (game.match)

How do I publish minigames? On open world minigames, does the seed change in every lobby? Is it possible to make menus to spend coins on items in the minigame like a shop? Is it possible to earn coins via custom minigames? If yes, how? I’m making a battle royale minigame, however I need to know these stuff so I can make my minigame based on the responses. (By coins I mean account coins, like the ones you get from daily rewards)