Google is rolling out a feature to fix or change your Gmail address (How To)

Google rolls out option to change Gmail addresses. Here's how to change your Google Account email address and transitioning to a new Gmail address.
Android Police

How to add an iCloud email to your Gmail account

Gmail supports various email providers, including Outlook, Yahoo, AOL, iCloud, and more. This feature is particularly handy if you want to manage all your email accounts in one place on your Android ...