New house, fiber-optic, how is installation done

Thank you - VERY helpful!

I am now asking myself WHY my homebuilder put the 3 Cat5 cables where they are, outside!? I will discuss this with them.

Yes, I am sure we got fiberoptics, up to 1000 Mbps, not sure about (never heard of) FTTP vs FTTN.

What is the "gateway"?? Is it some sort of a modem, or device that translates the fiberoptical signal to ethernet? Can I put that gateway in the garage (as well as the ONT), basically at the same location where my Cat5 cables are exiting the house (but inside)? I could easily open up some drywall inside, pull the Cat5 cables inside, and connect them to the gateway. Good idea?

If that is not a good idea because the Gateway (=distribution point, right?) should be in e central location in the house, is it better to run cable between NID and ONT, or between ONT and gateway?

Thanks again for any input!! I see a lot of rolled-up Ethernet cables on hanging lose outside on neighboring houses - I am sure most people did not know how all this works!!

Again - thank you very much!!  Let me make sure I understand:   

AT&T pole in front of house----fiber----NID----fiber----ONT----copper----Router/Distribution----Cat5----users   

with

1. NID outside on side of house (next to my coil of rolled-up Cat5 and Coax cables)
2. ONT inside house, garage OK
3. Router, ideally in central location in house

Now, with regards to the cable set up that I have (all cables starting outside of house, near future NID):

1. Coax-1 & Cat5-1 to LvgRoom
2. Coax-2 & Cat5-2 to Loft
3. Coax-3 & Cat5-3 to MstrBR

Big Question: Can the AT&T signal between ONT---Router run through a Coax cable? 

If yes, I have an idea: I could pull my 3 Cat5 and 3 Coax cables inside the house into the garage (which is easy), and then

• install the ONT in the garage (near NID outside)
• place the Router in the Loft
• then use Coax-2 to connect ONT to Router
• use Cat5-2 to bring Ethernet back to near ONT
• install splitter there to connect Cat5-1 and Cat5-3   

In this way I would have Ethernet in all my 3 desired locations, and the Router placed centrally in the Loft without having to change any cable, or run news ones!!

What do you think? Again, your feedback would be highly appreciated! BTW, meanwhile, I placed an order with AT&T for internet service 😉   

Got it, thanks: Technically possible, but of course, not preferred, not officially approved (and warranted).

We have an appointment on site with an AT&T tech next week, I will ask her/him about the adapter solution.

Running extra cables sounds costly (and insane, with drywall now installed after cables have just been run!), but I will inquire as well.

My goal of this whole exercise was/is, to save WLAN bandwidth by hooking up the 3 large (55", 65", 70") UHD TVs in the house to Ethernet - and thus leave WLAN bandwidth to all other internet users in the house. Is that good thinking, or overkill / inadequate for a regular 5-person family home with 3 teenagers?