How to find the files (.apk) of a certain app like Google Play Services I have a rooted device and I tried the find / -name &quot;*Play*&quot; command and got some files from com.google.android.gms and a couple of Playlists but nothing like Google Play Services.apk
I wonder if it is possible for an app to not have an .apk file and if this is the case is there any chance of finding the files associated with the app from the app name?
You won't need root for that, but can utilize the pm command either on-device from within a terminal, or via adb:
adb shell pm path com.google.android.gms | awk -F':' '{print $2}

will give you the full path including the file name, so you could use that to pull the APK from your device to your computer:
adb pull $(adb shell pm path com.google.android.gms | awk -F':' '{print $2})

To answer the other parts from your question:

every app has an *.apk file. Some might even have multiple (&quot;split APKs&quot;).
finding the APK by the (localized) app name is not trivial. You'd have to parse the entire app list to get the package names, use those to get the location of the APK as described above, and then use aapt to extract and match the localized name (I haven't yet found whether and if where Android might store that outside the APK). aapt usually isn't present on-device.