How to toggle MacBook's bluetooth on/off with only the built-in keyboard in OS Monterey
Scenario: in your Accessibility settlings you chose to turn off your MacBook's built-in keyboard if your bluetooth mouse is connected, but you left the mouse somewhere without disconnecting it, so you have no pointing device and can't figure out how to disconnect your missing mouse so that your trackpad will work. Here's how(I'm using MacOS Monterey)(No doubt you can do the same thing in later versions of MacOS but perhaps with a slightly different route):
>First, while you have a working pointing device, do this:
>In settings locate "Keyboard";
>Shortcuts tab;
> near the bottom of the shortcuts dialog box, enable "Use keyboard navigation to move focus between controls";
>Exit settings;
After keyboard navigation is enabled, when stuck in the scenario above, do this:
1. Press Command + spacebar;
2. When spotlight search opens start typing "bluetooth" (this opens a menu where you will see "Bluetooth" and "Bluetooth file exchange.app";
3. Use the down arrow to move to "bluetooth" and press <return> (this opens your MacBook's bluetooth settings);
4. Tab until reaching "Turn Off Bluetooth" and then press the spacebar;
5. Wait until Bluetooth turns off (it isn't instantaneous).
Note: If you need to turn bluetooth on, rather than off, and your pointing device is disabled, then after pressing Command + spacebar, highlight "Bluetooth file exchange.app" and press return: the system will turn bluetooth on. You cannot turn Bluetooth back off in the scenario described above unless you leave keyboard navigation enabled.