I once bought a router to use for my internet when I moved into my new house just to find out that it “wasn’t compatible” with Verizon’s service. I still have it (because I’m terrible about returning things). Is there any point in keeping it? Is there anything fun or interesting that I could do with it?
You could probably turn it into an extended access point or something like that. You could also set it up to be used in like let’s say a lab or something like that. If possible, check what router it is and see if you can put OpenWrt or something like that on it.
If not, collecting dust in a box isn’t a bad idea either, just if you decide to take it out again to clean it thoroughly.
Official guidance from Verizon is you can use your own router as a router, by setting your Verizon router as a modem only, then connecting it to the WAN port on your router. See e.g. https://kb.netgear.com/31100/How-do-I-set-up-my-Orbi-system-to-work-with-Fios
Unofficially, it’s fine. You can just use your router. The modem is in the white box on the wall (the ONT) with fibre on one end and ethernet on the other. I’ve been running my router directly to the ONT for 3 years without issue. It just works fine.
“Not Compatible” usually just means “We’re extracting a monthly fee from you to use out provided router”. Most likely, if you were to poke around, you could turn your ISP router/modem into a dumb modem and disable the inbuilt router, then connect your (better) wifi router to that.
