Allow App Installations from Unknown Sources - Motorola
Your device and personal data are more vulnerable to threats such as Ransomware from apps downloaded from unknown sources. Here's some additional info about downloading from unknown sources and protecting your device against Ransomware.
Android® 8.x & higher
From a Home screen, navigate to Settings .
Tap Apps & notifications.
Tap Special access.
Tap Install unknown apps.
Select the unknown app then tap the Allow from this source switch to turn on or off .
Android® 7.x & below
From a Home screen, navigate to Settings.
From the Device Administration section, tap on Unknown sources switch to turn on or off.