I need to open a specific port on my mac client (because when I try to connect from server it says "target machine actively refused it ").My problem though is I cannot find a way to add a specific port on my latest Mac OS.

I go to system pref->securtiy &privacy->firewall-> turn it on (FWIW connection didnt work when I had turned it off)->Firewall options->"+"

This gives me an option to add some application but not a port .Can someone point me to the right place to add the port?