google play services – Is there *full* documentation for adding Admob to Unity anywhere?

The official documentation leaves out really important steps.
Adding ‘cocaopods’ and ‘Google Play Services’
They are just listed as prerequisites without even any links.

Another confusing thing is that, elsewhere I have seen that apparently I dont also need the Unity Google Play Games Services SDK for Admob to work. But in that case then why is ‘Google Play Services’ listed as a prerequisite on the official docs?

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