The class-character can also attempt stuff that is not covered by an ability of their class. The playbook one has to stick to the moves of its playbook. That is why I mentioned TRRPG as a giant state machine earlier
But, this is inaccurate.
The typical thing for a playbook is, you, the player, narrate trying to do whatever you want. If/when what you are trying to do matches a move, then we roll dice for the move.