Since you're using internet using UT-300R2U, it has to be a modem cum router. Here is what you can do: Buy a Wi-Fi router. Put your UT-300R2U in bride mode, so that it works only as a modem, and connect UT-300R2U to your router.
Or, you can buy a modem-cum-router (WiFi) and sell your UT-300R2U...