You have to make this, test it and figure it all out. I am running into folk that think this is a supportable product. They often get upset it isn't.
So there are antennas but the loss down the cable to your receiver blows up the idea. What seems to work is a WiFi Client (there are so many out there) up by your antenna and Ethernet down to your LAN. You could get your wired LAN working first then put a WAP on that LAN.
If all this is Greek then you may have to give yourself time to learn more about WiFi and networking.
Bob
I have a local wifi hotspot near me that is not quite strong enough. I would like to have a rooftop antenna that I could hook up to a wifi router to rebroadcast to my devices. I would appreciate any help. Thanks.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic