How do I locate my archived emails on in iPhone Mail app

Hello Netaneta13,

The Archive folder is one of the many folders of an e-mail account. To view it, tap the "<" icon at the top left of the screen until you see the list of Mailboxes. Next to the name of your provider (iCloud or other), expand the list by tapping the ">" icon to see the Archive folder of that account.

How did you archive the messages? Where did you store the archive? You likely need to import those back into mail.