The antenna I put in the attic which rotates has it's coax cable going to the antenna port on this:
https://www.amazon.com/gp/product/B01J6A6H74/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
The Fire TV Recast cube has two TV outputs you can coax directly to two different TV's. It's output ports are tv1 and tv2.
You setup the Recast cube via your phone and you get 500gig of cloud recording from Amazon with it.
I also have a Toshiba fire TV and my Samsung has a 4k fire stick in it. And I also have a separate antenna on my Toshiba.
My first or the basic menu on each of my tv's is the firestick menu.
From there I go to either downloaded apps, live tv via antenna, live tv via fire cube and tons of other things.
Right now I'm watching Oak Island.
via... firestick Home, cursor down to my "FUBO" app, click on the app, go to it's tv guide menu, cursor down and click on the history channel.
On my fire tv in the firestick menu I can go to settings and select what ever hdmi tv port I wan't or other tv inputs.
I happen to have a google crome thing on one hdmi port and a netgear mirror on another port so I can mirror to my tv what ever I want.
We can set my phone in front of out regular tv with it's camera pointing at us and mirror what's on the phone to our big livingroom tv.
We then can video call my daughter and watch them(baby grandson) on our big screen tv while they do the same.
.... your rotating antenna goes to the fire Recast. I think it broadcasts to both my fire stick on one tv and the toshiba fire tv.