There are plenty of guides available. I don't know your mother tongue, but seeing your last name, I assume you may be speaking German. Take a look at these German language guides:
I do speak German, thanks for the links.
https://www.it-management-kirchberger.at/manuals-tutorials/server-centos-7/postfix-mailserver-vimbadmin/postfix-amavisd-new-clamav-spamassassin.html
I could not find anything there related to multidrop or "catch all" mailboxes.
https://www.dokuwiki.tachtler.net/doku.php
Nothing like that there either.
https://dokuwiki.nausch.org/doku.php/centos:mail_c7:spam_6
This is a huge document with little introduction. It seems to be mostly about fighting spam. I did not find anything like the setup I described. Regards, rdiez
