How can I get the value of an input from the parent schema from within an action?

Section::make('User Information')
  ->schema([
      TextInput::make('first_name'),
      TextInput::make('last_name'),
      Radio::make('flag')->options([
          'Admin' => 'Admin',
          'Student' => 'Student',
      ])->required(),
      Action::make('test_action')->schema([
          TextInput::make('additional_information')
              ->hidden(fn ($livewire) =>$livewire->data['flag'] === 'Admin'),
          
          TextInput::make('another field'),
      ])->action(function () {
          return true;
      })
  ]),