Discovering Discovery Mode

question

#1

Greetings, fellows of the hammer.
Questions about Discovery Mode from Hard Suit.

Tl;dr How much/what is prepped and how much is Discovered?

I’m not clear if the GM has Anything prepared in terms of party composition, or if Everything is rolled from the tables in real time.
The youtubes I’ve watched don’t give any clue if the players have chosen character names or if they have rolled on a table. Is it totally roleplayed in the moment?

I’m going to be doing something like Kane’s Kiln “Hard Suit in Pyros” and use the Discovery Mode in my own world setting, so I’m trying to understand what principals I can apply anywhere and what is firmly fixed in the Atria setting in the book.

I’m wondering if I need to write my own tables suitable for my setting, but that then seems like it’s been designed and not Discovered.

Anyone used Discovery Mode ? Any tips?