i do not want to save every email but it is difficult to delete emails twice one at a time.

Please provide more information. Is this a Gmail account? Do you actively use the Important folder? If not Gmail, who is the email provider?

yes gmail and i first noticed the important folder after a tech made the saved emails folder go away. These emails were never marked important by me. I save only important emails (not sales or spam) in separate individual folders.

Those messages are marked "important" by Google, their attempt to be "helpful", I guess. It also shows that they are mining your email content. You can control the Important flag behavior to a degree on the Gmail web mail page. See the following article:

https://support.google.com/mail/answer/186543

I adjust the "Change your importance marker settings" as decribed above, and also un-subscribe that folder in Thunderbird so I never have to see it (right-click on the account name in the Folders List, choose "Unsubscribe", and un-tick the "Important" pseudo-folder.) Also, unsubscribe from "All Mail" if you haven't already.