A router that supports wisp operation able to use wifi as an internet port might be better suited to what you have in mind. Using a standalone modem and router.

How Connect Two Wifi Router Without Cable Wds Settings 100
How to connect wireless router without modem. Plug the other end into any free port on the first router other than its uplink port. To do so you will need to connect your broadband modem to the router. Connect your modem to the wall outlet you get your internet through. Wireless router setup without modem the wndr3400 can serve as a repeater but only the main network has security turned off. Connect the other end of the ethernet cable to the wan port on your. Connect an ac adapter to your modem and plug it in.
Connect a second wireless router. Herere some very good reasons why you should use a separate router and modem. At this point you can proceed to configure the second router. Routers and wireless routers enable you to share your broadband internet connection with multiple devices. However the ultimate way of utilizing your isp provided internet connection is by using a standalone modem and router. Connect the router and the modem with an ethernet cable.
Connect your router to your modem. Reset the second router to factory settings and connect it to the main router via ethernet cable. Select wireless settings and write down the channel wireless mode and the ssid. Make sure to note your passwords and security mode wpa2 wpa or wep. Plug one end of the cable into the new routers uplink port sometimes labeled wan or internet. How to connect a router to a modem.
You can connect to the internet using the modem alone or the modem router combination device. Connect an ethernet cable to the ethernet port on your modem. For best results place your router near your modem. A second router that doesnt have wireless capability must be connected to the first router with an ethernet cable.