The APK file called Google Account Manager 7.1.2 (Android 6.0+) is currently hosted on all major APK sites. It is offered officially by Google LLC. The APK is offered in several versions. It supports only Android 6 and higher, as mentioned above. It supports No Dpi and sizes up to 6.3 MB. You can install it off storage also using the .APK file.
The Account Manager is one of the primary functionalities on an Android Smartphone. Any and all devices running Android must have an associated Gmail account. This same account is used to authenticate every functionality on the device. Even if you factory reset the device, Google remembers the device you used last and you need to enter the account details used earlier on the device.
Keep all Account Related info for the device, restore when needed, keep things in sync across all your device using the same account.
It uses the same Google Gmail Account used. If you have more than one address then you need to use the same henceforth.
One device cannot use more than one Gmail Account. But one Account can be used to use as many devices as possible.
It is often better to use another account if you want to use a separate account and not use the synced items from another device usage.
Use the SD card to install the package offline and transfer it between devices, although it comes packed with the Android and Google Services.