Google Service account for Google analytics

I am not sure which part of the documentation you mean?

Google does not have Compute Engine default service account

“Service Account
In the left sidebar, you should see Credentials link, click it the go to Create Credentials and then Service Account Key. In the form select “Compute Engine default service account” and JSON. Creating the account should automatically download a JSON file to your computer (we will use it later). One last thing we will need here is service account email”

from https://wpadverts.com/documentation/google-analytics-integration-paid-addon/

Google is often changing the interface so the exact steps might be different, but i am checking their interface right now and it seems the Compute Engine account can still be created without any problems.

I understand you already have the API Project created here https://console.developers.google.com/, if so then see the screenshots below, they are both in Polish but if you will click the same links in the same order you should be able to do it.
https://www.dropbox.com/s/brt710j0926x9pf/wpadverts-ga-1.png?dl=0
https://www.dropbox.com/s/lb0tq2y56dah10z/wpadverts-ga-2.png?dl=0

Note the above links will be removed in about 7 – 14 days.

Ok thanks . I check again

Is compute engine a role ?

As a role in WordPress? If so then no it isn’t.