How to configure postfix to only send emails?

Question

postfix

You may want to immediately write "hey, why don't you know how to google?", but read to the end!
So, there is a domain name and mail is configured on pdd.yaandex.ru to send and receive letters for our company.
Question: Is it possible to set up a mail server on your dedicated server to send emails from a web application (requests, notifications, etc.) so as not to run into the limits that yandex has?
It seems to be a null client configuration in postfix, but I can’t find on the Internet how to configure it without relayhost.