For better security, Android phones will block app installations from unknown sources. Meanwhile Android provides us the options to manually enable the installation of apps from third-party Android markets or sources. For example, you can allow installations of apps from unknown sources on Xiaomi phones, just as an example. Android powered Huawei phones have similar options. On Huawei phones let us have more flexibility over the app installation. You can even allow installations from certain third party stores or resources, and disable the permission anytime you like. You can see more details below.
Other than ‘install apps from unknown source’, it has a new name on Huawei phones. It is now called ‘install unknown apps’. And here’s how you can find that option and enable it on Huawei mobile phone.
Also in Settings like any other Android phones. Head to Security & privacy > More > Install unknown apps > Files > Allow app installs. Set it to on so downloaded apps, APK files, can be installed from the stock file manager app on Huawei mobile phone.