Too many emails

[Jonbrick]

I am swamped with over 21,000 unread emails and more pile in every day. So many are from politicians across the U. S. in states where I have no interest. And they all want money! My limited senior income money! In the past I've selected two or three thousand junk emails at a time to delete, but I still can't get ahead. How do I wipe all the emails, while saving selected ones in my mailboxes? Help! Any and all suggestions are appreciated.
BTW I'm using a 2015 27" iMac running macOS Big Sur, version 11.7.10

 

[MacsBug]

You may want to try a couple of rules for mail. Perhaps all mail that has the word Donate in the body gets moved to trash.

You can read more about Mail Rules here: https://support.apple.com/guide/mail/use-rules-to-manage-emails-you-receive-mlhlp1017/14.0/mac/11.0