The way it is usually done is they run the fiber optic cable to the house, and install the Optical Network Termination or ONT at or near the service entrance for the premises. That can be indoors or outdoors, generally your choice. Included is the power supply and battery backup unit, which will be indoors, and needs a wall outlet.
A coaxial cable will then be run from the ONT to where the current Cable Splitter is located. The cable service connection there will be disconnected, and the splitter will be replaced with a wider bandwidth, bi-directional splitter (MoCA uses frequencies well above the normal cable TV channels to distribute the internet, so the existing cable splitter generally won't work).. The existing wiring from the splitter to the various rooms in your have is usually left in place and should work fine. A new Coaxial cable will also be run from the splitter to wherever the router is going to be located unless there is already coax there.
There are no setting involved. Just some new equipment, and some additional coaxial cable. If you want the ability to connect in rooms other than where the Set Top Boxes will be initially, you need to tell the installer. Generally they don't connect the coax to the splitter unless there is going to an STB or Router on the other end.
