User Manual TP-Link ARCHER A6 V3 AC1200 Gigabit WiFi Router

Yes you would put this in AP mode.

If you have internet through your phone service, then plug the WAN cable to the phone jack and to the router, press the wifi button in back and you are good to go!

Yes, very well. You can easily see your devices and any unwanted devices and block them.

Yes, in the WAN settings.

Yes but you would be better off with a range extender. If you were to use the router then you would need to make use of WDS.

This does allow more then one Device to be hooked to it works great

They are fixed vertically but just pull out and they do remove after you have installed.

Yes, you can apply MAC address filters to only allow specific devices by their MAC address. You can also limit by IP addresses but this would require the devices you want to allow access to have a static IP.

No, your modem is what needs to be activated by your ISP. This router connects to your modem via Ethernet to provide your home with reliable, dual-band AC1200 WiFi connectivity.