Problems opening files from an .apk

As the title says, I extracted all the files from an .apk and selected the folder in which I extracted the files as a project in unity, and stuff worked out fine with the “assets” and “packages” folders showing up, but I’m unable to open any of the files, not to mention most of them don’t have file extensions. I opened the metadata files with notepad too, but didn’t see anything useful leading to the file extension. What could have gone wrong?

I am not sure if I understood your exact issue, but what you ship into the apk itself its not the full unity project, you simply cant unzip an apk and open it with the editor, Imagine having access to the source code of every project simply uncompressing an apk. what exactly do you want to do?