The one on the top left is the fiber hub. That’s the main feed into the building. The one below is a terminal which connects to all the fibers coming out of the greenish conduits. The four gray boxes are individual ONT which are probably for various data/phone connections(elevator/fire alarm/faxes) for the building.

Your ISP will likely be installing a ONT plus a router or an ONT/router combo unit. If it only has one LAN port you just need to purchase a ethernet switch. The router or ONT/ router combo they install will handle the DHCP. I honestly never heard of an ISP not providing some sort or device without a routing function. Who is the ISP?