Dear friend!
I think you're missing an external port number, which is the port number for external network packets from the WAN port.

When configuring the IPv4 port mapping, you need at least three parameters: internal IP address, internal port number, and external port number.
Currently, your website port number is equivalent to an intranet port number.
192.168.18.5 is the internal IP address.
The database port number may not be used here. Because when an external user accesses your site, the server software automatically accesses the database.
For more details, please click the link provided by chenhui.
Thnaks!