A few days ago I tried to synchronize my laptop with the desktop computer, and on the laptop, it was IMAP server and on the desktop, it was a POP server where all my emails were stored with the created folder with emails.

I don't know what I need to do to upload somehow this folder to newly created account with IMAP server. No one said that before transferring from POP to IMAP server I need to copy my emails, just explaining that you need to remove old acc and create new.