What router only has 2 ports? What is the make and model of the device?
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You can purchase a switch to put on the LAN side of the router to share the network to your other devices.
P.S. You are not confusing the ONT (converts fibre signal to Ethernet) for a router by any chance? Your router should be a white cylinder, or a black box; either has 3 or 4 Yellow LAN connections.
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