There should be a keyboard shortcut to toggle in & out of VoiceOver
option & that is shown in Accessibility section of System Preferences.
{There may or may not be other Accessibility causes behind present
circumstances; if one action was due to accident, others may have.}
A more complete set of information on VoiceOver (that you may have
gotten to work by accident) is covered in the section which follows:
VoiceOver keyboard shortcuts - Apple Inc.
This appendix lists VoiceOver commands and gestures, organized into categories.
General commands. ... Learning about keys, keyboard shortcuts, and gestures.
https://www.apple.com/voiceover/info/guide/_1131.html
{Command + F5 in some configurations may toggle or access VoiceOver in Sys Preference
and note there may also be a 'check-box' to enable VoiceOver with this preference panel.}
OS X VoiceOver Commands / Keyboard Shortcuts Cheat Sheet ...
OS X VoiceOver Commands / Keyboard Shortcuts Cheat Sheet. Last updated: January 21, 2014.
This page shows the OS X VoiceOver commands in HTML, which were previously ...
lab.dotjay.com/notes/voiceover-commands/
• While 'safe mode' has several useful purposes, right now I'm not able to detail them.
I've used it on occasion. Sometimes to boot into Safe mode, then restart normally, helps.
Be sure you have actually gotten restarted in Safe mode. You'd need to login admin PW.
• Use safe mode to isolate issues with your Mac - Apple Support
Not sure if you could try a reset of NVRAM to resolve some issues, as
certain settings may be removed or set to default once either an SMC
or NVRAM reset, invoked. {The SMC more involved with troubleshooting
and several steps can be done prior to that reset to see if they help, first.}
• How to reset the System Management Controller (SMC) on your Mac - Apple Support
• How to reset NVRAM on your Mac - Apple Support
Not saying any of these are a solution; mostly the 'Safe mode' on startup can help in
troubleshooting and may itself effect a self-repair or default re-set to original setting.
Deeper issues may involve starting in macOS Recovery to use Disk Utilities; or repair
the system, reinstall, or otherwise use TimeMachine backup to restore functions.
And the VoiceOver info was added because you mentioned having it On, without cause
or direct to any specific purpose. ~ Some accessibility features are more easily toggled
off/on, and kids can easily turn the screen into a white on black chalkboard with 2 keys.
Good luck & happy computing! 🙂