I want to use the default e-mail on my new Mac Pro--I do not want Google

When you create an Apple-ID, Apple gives you the matching yourAppleID@iCloud email address.

You can use that or any other email address an email service provider will let you set up.

Apple Mail will set up many different accounts for you. Google gmail is available in Apple Mail, but is NOT required for anything.

What is your desired email service provider?

Are you seeing an aggressive ad for google mail instead of Apple Mail?