Gmail is very popular, free to use email service provider. This guide will help you setup the Mac Mail program to access your email, rather than rely on the web interface.
Before You Begin:
Verify Password Before setting up, take a moment to visit the web-based version of your email, and try to log in (sign out then back in if you need to). You will need to remember your password in order to complete setup.
macOS handles your Internet Accounts, like your Yahoo! account, in a central location in System Preferences. Then, programs such as Mail get the settings from there automatically.
Select the Apple Menu, then select System Preferences.
Select Internet Accounts.
Select Google.
Google requires authentication through your browser. Select Open Browser.
Type in your Gmail Email address and select Next.
Enter your Gmail Password and select Next.
Google will ask permission to access your accounts, select Allow.
Internet Accounts will ask what aspects of your Gmail account to access. The defaults are fine, select Done.
Your Google account is now setup on your Mac.
Open the Mail program from your Dock or from Applications to read and compose email.