I'm going to assume your apartment’s ethernet wiring is isolated to only your apartment. IOW, it's not wired/routed to every other apartment, and where the landlord provides internet service to all the tenants over those wires. They’re both distinct possibilities, but only your landlord can confirm that one way or the other.
But if we assume your wired apartment is indeed isolated from your neighbors, then you simply connect the modem to your router, then patch a LAN port on the router to one of the ethernet ports in the apartment. Now every room w/ an ethernet port will have access to the router. And they all share the 60Mbps bandwidth provided by the ISP.
NOTE: It’s also possible your apartment has a junction box where all those wired ethernet ports converge at a switch. You could hook up the router there instead, if it proves more convenient. But since many ppl use routers w/ integrated wireless, it’s not always conducive to a good wireless signal.