How many custom domains be hosted per GCP account?

Solution 1:

I just want to use @AxyzTxyz.com email id for IAMs

If you want to use a business email for your Google Cloud Projects, then you need to set up a Google Cloud Organization. This requires either a Google Workspace or Cloud Identity account setup with the business domain name you wish to use.

Creating and managing organizations

Since you already have a Google Workspace account providing your business email, setting up an organization is easy.

Organization setup wizard