Credit source: https://www.wikihow.tech/Extract-APK-File-of-Any-App-on-Your-Android-Phone

This wikiHow teaches you how to extract the Android Package File (APK) of an Android app so that you can install the app on another Android phone without having to use Google Play. This is helpful for installing old apps on new phones, installing apps scaled for small screens on larger devices, or testing compatibility with newer and/or older Android devices.