Yes , but it depends. I currently have Verizon Fios, so I think it's the same setup.
I initially ordered Fios without a router, with Ethernet directly from the ONT. This definitely works. Connect the ONT's Ethernet cable directly to the internet port. You might have to call the provider to 'release DHCP', for it to work, if replacing another router, or it should work on its own overnight.
If the account is set up so you're required to use their router, then you still can disable WiFi on their router and connect this to one of the ethernet ports on the router. Once you set it up initially via the phone app, change the connection type to 'Bridge Mode' (From the app is simpler, but it can also be done from the desktop).
Note that this is more or less the same with any other WiFi router.
If you then add more mesh nodes, then there isn't anything else special to do here. It will work.