Is there an android GSI to enhance user focus?

Is there an android GSI that limits the phone so user can focus ?
I want the phone to be limited to just dialing, alarm, calendar, … to be just as useful as an old Nokia phone.

Just use an app on top of your current Android version, there’s no need for system level special ops

It’s easy to just uninstall the app.
I also thought it would be cool if my phone behaved like an old nokia phone.