“OpenBSD’s man pages are good” is a meme for a reason: https://man.openbsd.org/pf.conf.5 https://man.openbsd.org/pf.conf.5 That + https://www.openbsd.org/faq/

“OpenBSD’s man pages are good” is a meme for a reason: https://man.openbsd.org/pf.conf.5 https://man.openbsd.org/pf.conf.5 That + https://www.openbsd.org/faq/pf/example1.html https://www.openbsd.org/faq/pf/example1.html were more than enough to get me going.