Fiber internet (at least where I live) is just a TCP/IP connection. You could even connect it straight to your PC and it would work.
So, I use a SFP module that it suitable for the wavelength and mode of my fiber connection, and plugged that in an Ubiquity Edgerouter. In case of my ISP I had to configure a VLAN on the external interface, as they use separate VLANs for internet, TV and telephony. Once you configure the VLAN, the router will receive an IP address over DHCP and you'll be online.
So, I use a SFP module that it suitable for the wavelength and mode of my fiber connection, and plugged that in an Ubiquity Edgerouter. In case of my ISP I had to configure a VLAN on the external interface, as they use separate VLANs for internet, TV and telephony. Once you configure the VLAN, the router will receive an IP address over DHCP and you'll be online.