How do I stop all the junk in my Apple mail?

Short answer - you and I can not Stop it 100% of the time.

Once and e-mail address has been harvested from a Social Media Sites ( example ONLY ) , Software Developers who have had a Data Breach - the e-mail address is Sold and Traded to " Bad Actors " Spammer.

The Best we can do is react to this by using some of the methods you have already implemented

An often suggest Mal Add on is a paid one called and located in this link >> https://c-command.com/spamsieve/

I have test my own e-mail addresses and those of my Family on this site and was blown away by my e-mail address was involved in 2 Data Breaches

One from a well known Third Party Software Developer and the second from my own Internet Provider ( ISP )

https://haveibeenpwned.com/

https://haveibeenpwned.com/PwnedWebsites

EDITED

Follow on - >> Frank

Try Logging into your e-mail accounts using your Web Browser

Some e-mail Providers do offer the ability to Block Senders directly at the Server Side.

Yes, it does mean manually inputting the Addresses and or Domain Names

But, if done properly by you, the Junk e-mails will never reach your Inbox on Apple Mail

refer to image below from my Wife's E-mail account with our ISP

Welcome and as usual Do come back to the Apple Support Communities ( ASC )  in the future  if or when additional questions may arise.

FWIW, I have never received any "Junk" mail and at most I receive perhaps 2 or 3 Spam emails a week. But, glad to see your answer was solved.

Welcome and thank you too @ frank_the_snake_master_01