A:AnswerNot don't necessarily need an ethernet cable, you can connect to this device via wifi or ethernet. however, you do need an ethernet cable to connect this router to a modem. You don't need to pay monthly for this router.
A:AnswerThe ASUS RT-AC67P is a dual-band wireless router that supports AC1900 Mbps speed. It does not have a built-in fibre optic modem, so you will need a separate device to connect it to your fibre optic internet service provider. You can use the router's WAN port to connect to the modem's LAN port with an Ethernet cable.
A:AnswerNo, you can't.
It has a USB port but the firmware does not allow the selection of the USB as the WAN port. (see attached image). RTAC86U has this option although is much more expensive. (see attached image
