Google Play is the place we can find, download, update, install, uninstall all kinds of apps and games on Android devices. If you intend to install applications from other sources, the installation will be blocked unless you have changed the security settings on the phone to allow the installation of unknown apps or apps from third-party sources. Today, we will use a itel mobile phone in the demo to show you how to install unknown apps or apps from third-party or unknown sources on itel mobile phones and other Android devices.
Launch the Settings on your itel phone, proceed to Apps & notifications > Special app access. See below screenshot.

On this Special app access screen, locate Install unknown apps.

When you on the Install unknown apps screen, you will see a list of apps on your mobile phone. By default, they will be set to ‘Not allowed‘.

Choose any apps from this list, then touch the toggle to enable ‘Allow from this source‘ , you will then find its status turns to ‘Allowed‘ which means you can run this specific app to find and install apps downloaded or received from third-party sources other than Google Play Store. For example, if you have allowed Chrome to install unknown apps, you can download apps from third-party websites onto your phone and directly install the app from the Chrome browser. When you saved apk files to the File Manager, grant the file explorer app the permission, so you can install apk files from there.

But still I can’t download anything and why is that…
Yet still can’t install any app
It will pop on the screen
Like
phone policy does not support
Can’t still install app on my phone