Email problem resolved. Here's how.

[ananda]

After doing some digging, I learned that the yahoo email service
works find on the app version.

On my Macbook, I opened the mail icon on the app page and it works.

Then I simply moved that icon to the dock, and now the email page
opens in the large computer-scale format so that I can do all the
formatting, cutting, pasting, and everything that I used to do.

Thank you to everyone for pointing me in this direction.