How do I get it?

Am I missing something? I couldn't figure out how to properly exit the game (from the main menu) when playing on steam deck. I know I can use the steam menu and choose "Exit" there, but the message box about losing unsaved progress suggests that this is not the proper way to exit the game. Solved it by mapping ESC to one of the back grip buttons, but I think there should be a more obvious way. Also, I almost missed Fowlist Mode, is this accessible in some way other than mapping P to some button or opening...

I have completed this game and would like to start again from the beginning without any saved data. How do I do this please?

Although I haven't finished it on Switch, this is a really good platformer. It isn't brutally difficult, yet also isn't a walk in the park. Recommended.