It might be a dumb question… But… I package my game with the option “Android (ATC)” and it was successful. Then I entered the folder and the executable that was in that folder sent a file with the extension “.obb” to my phone. The file shouldn’t have the “apk” extension, so I can install the application? I’m really confused and I don’t know what do to. Did I do something wrong?
Hello luisbento
If you can enable – Project Settings > Android >Package game data inside .apk? – not enough obb file. But disabled again before upload “Google Play”. Because “Google Play” not allow larger than 50MB .apk file. You will need the obb file here.

And why doesn’t the application get installed on the device after the installation?
Is the usb debug mode turned on?
Yes, it is
Android 9 doesn’t allow installing over USB (or at least I couldn’t get it to work).
I couldn’t test my game because of the missing .obb error.
This solved my problem! Thank you very much!