Your ONT has a manufacturer's name and model number. That information would be very helpful. Also so would the name of your ISP and the capacity plan you are paying for.
You don't need any adapters. You just need to work out how to configure things.
You will have two routers n your network.
Two routers on your network can cause headaches. For example, you can end up with local address problems. Among other things, the other router can misdirect addresses that the Netgear router usually handles, such as routerlogin.net or the usual IP address for a router, 192.168.1.1.
Unless you have specific reasons for using two routers – to create two separate networks for example – it is often easier to use just one router and then to set up the second router as a wifi access point. Netgear advises this, as does just about every site you will visit.
It may be possible to put the modem/router into modem only (bridge) mode and then to use the second device as the router.
What are you trying to accomplish with your R7800 that you cannot do with your ONT?
Excellent question.
Which features are on the R7800 that aren't on the ONT/router? After all, the R7800 has not, thankfully, gone down the Circle./Armor road. But it does have Anywhere Access that may, or may not, be on the ONT.
