From how I read this diagram, if you are able to get a 1 Gbit plan then it will be either cable or fibre. In that case they will install a Network Termination Device which is the actual device that converts the signal into Ethernet. From there you can connect to your own WiFi router, or the NF20Mesh (but its modem functionality is unused).
It might be best to call the ISP to confirm.
From how I read this diagram, if you are able to get a 1 Gbit plan then it will be either cable or fibre. In that case they will install a Network Termination Device which is the actual device that converts the signal into Ethernet. From there you can connect to your own WiFi router, or the NF20Mesh (but its modem functionality is unused).