Tecadmin published a tutorial about installing Dovecot on Ubuntu 20.04.
How to Install Dovecot on Ubuntu 20.04
Dovecot is an open-source service for IMAP and POP3 on Unix-like operating systems. It focused on lightweight and secure mail server available for most of the Linux operating system. POP3 (Post Office Protocol 3) and IMAP (Internet Message Access Protocol) both are protocols works as message accessing agent.
How to Install Dovecot on Ubuntu 20.04