How to find the sideloading options on an Oppo. Chrome), tap it and select Allow from this source. Find and tap advanced options or special app access. If the above path doesn't work for you, try the following:
Tap on it and then select Allow from this source.You should be presented with a list of apps.Scroll down and look for install from unknown apps.Find the Security & privacy option and tap on it.While there could be some slight variation in exactly where you'll find this setting on your Android phone, it's usually buried within the Security & privacy or App menus.
Most Android skins will present you with a shortcut to this page when you try to get the process done alongside a series of warnings.
If you have tried to sideload an app before then you will be familiar with this menu.
