I installed fedora 29 as a server for an office of windows clients

The net modem is provided by Spectrum.
It has another modem hanging off it which has all the windows machines on it.
These are wireless and use dynamic IPs.
(I think Class B is used on this modem as one address is
The fedora samba server is directly off the Spectrum and is using Class C.
The address is - weird the gateway is

Anyway the clients are not seeing the samba service.
I believe that I may need to do one of two things.

Do I need to set my netmast to (now
if so, how do I do that???
Do I need to go with dynamic IP and get on the other modem?
I have never used dynamic IP on a server so have no idea how to do this.
Should I be looking at something else entirely?