You have to own the IP, and map the RPi to the standard ports (80/443, likely have to set that up from router). Alternatively just do x.com:yyyy if you don't

You have to own the IP, and map the RPi to the standard ports (80/443, likely have to set that up from router). Alternatively just do x.com:yyyy if you don't mind (though you probably do for an external facing website).