Play Protect helps keep your phone secure by automatically scanning your apps, including sideloaded apps, to check for potentially harmful apps (malware).
If Play Protect finds a potentially harmful app, it stops the app from running and warns you so that you can uninstall it.
To see the results or to rescan:
Play Protect is on by default.
To learn more, read Google's help.
If you’ve scanned your phone to confirm there aren’t any potentially harmful apps but your phone seems slow, troubleshoot the issue.