No problem! Better safe than sorry.
For Mac:
For copies of Flash Player distributed by Adobe, you can run our uninstaller:
https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html
For copies of Flash Player distributed by Google (as a built in component of Chrome), a future Chrome update will drop support for browser plug-ins and remove Flash Player. As long as you have automatic updates enabled in Chrome, you don't need to do anything.
For Windows:
For copies of Flash Player distributed directly by Adobe, you can run our uninstaller:
Uninstall Flash Player - Windows:
https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html
For copies of Flash Player distributed by Microsoft (the built-in copy on Windows 8 and higher for IE and Edge), you can
install this optional Windows Update.
Microsoft Update for Removal of Flash Player
https://support.microsoft.com/en-us/help/4577586/update-for-removal-of-adobe-flash-player
At some point in the future, Microsoft will make that update mandatory. If you do nothing and have Windows Updates enabled, Microsoft will automatically remove Flash Player from your system at the point that they mark that update as mandatory.
For copies of Flash Player distributed by Google (as a built-in component of Chrome), a future update of Chrome will remove Flash Player support and the bundled copies of Flash Player.