email folders on MacBook

[lori5060]

oops....think I posted to incorrect forum..

I'm house cleaning!!

Macbook pro..mail folders on left side.
Inbox, drafts,sent, junk and trash all easy to understand.

What is archive folder for? I see I have tons of emails In there and seem to be dupicates of what I have already. Found I could go to iphone/ipad settings, accounts&passwords, ea mail, advanced …..
move discarded messages into: change discarded messages goes to delete mailbox and not to archive mailbox. How do I do the same on macbook pro?

Also in this section under mailbox behaviors: done on iPhone and iPad....
I see archive mailbox…it originally had all mail but I changed to starred…so am presuming that nothing should go to archive anymore unless I star it and I don’t do that at all. But when I went back into to check, I see it has reverted back to ALL Mail goes to archive box. I was careful to save and click done when finished. Am I doing something wrong or is that the way it will be?
can this be done on MacBook?

What is smart mailboxes…today?

Under section: on my mac….
What is important mailbox? Seems to have a lot of duplicate emails. Can I change this?

I know I can hide these folders but want to empty them before that!