On your device (Android 11+), find the Build number option and tap it 7 times to enable developer options. You can find this in these locations for the following devices:
Google Pixel
Settings > About phone > Build number
Samsung Galaxy S8 and later
Settings > About phone > Software information > Build number
LG G6 and later
Settings > About phone > Software info > Build number
HTC U11 and later
Settings > About > Software information > More > Build number or Settings > System > About phone > Software information > More > Build number
OnePlus 5T and later
Settings > About phone > Build number
Connect your device to the computer with the downloaded file and transfer the file to your mobile device.
Go to your device settings and tap Apps & Notifications (or Apps in older versions of Android)
Tap the three dots in the upper-right corner
Tap Special access
Tap Install unknown apps
Tap whichever web browser you use
Turn on Allow from this source