@chudak
If NGINX runs on a device behind pfSense within a private subnet you have to forward 80 and 443 to it, of course.
Firewall > NAT > port forwarding.
Add a rule:
interface: WAN
protocol: TCP/UDP
destination: WAN address
destination port: HTTP
Redirect target IP: NGINX IP
Redirect target IP: HTTP
Add a second rule for port 443 (HTTPS).
Ensure that the webGUI is not listening on port 80/443. System > Advanced > Admin Access > TCP port