Hmm, the only "native system backup facility" in Android is a backup of app data (not the apps themselves) that Google offer, currently called "Backup to Google One" on my phone. Personally I don't really trust that: it currently tells me it's backing up half of my apps, but doesn't provide an obvious way of telling which half. Is that the thing you are using?
If not I suspect it might be a manufacturer app (though I will disclose here that Android 6 is the only Android version between 1.5 and 11 that I've not used myself, so there's always a chance there's a feature of that version specifically that I've not met!).
To be honest the only wholly reliable way of backing up both apps and their data that I know and have used requires root (Titanium Backup). I did, a long time ago, use MyBackup Pro, but that required root to back up some things. There's an app called Helium in the Play Store that can back up most stuff to a computer (it uses adb backup under the hood, though some apps can declare that they should be excluded from that). I don't know about Google Drive, but as I recall it's a manual process rather than automated. I gather that it doesn't work well with modern Android versions, but it should be OK with Android 6 (I used it to migrate data from Android 5.1 to Android 8 when Google's transfer tool on my Pixel failed to work).