Adding Apple Airport Extremes to a Netgear C7000v2

I have my Nighthawk modem/router set up in my basement, where my computer is setup, but I want to get a good reliable wifi signal throughout the house.  I have a cat5e cable running up to the second floor of the house and have a d-link extender hooked to that, but it just seems like i've got a lot weak spots throughout the house and I just dont have good seamless handoff bwtween devices.  I have recently gotten a couple Apple Airport Extremes 6th gen, so I would get the ac wifi band.  

For some reason the Airports won't join the network, they just keep wanting to create a new network and creating a new network causes conflict. I have tried disabling the SSID Broadcast within the Netgear genie, but that still made the Airport go into Bridge mode.  I have also turned off the Router function in the Advanced settings, but when I did that my computer, Mac Pro 5,1, wouldn't even connect through an ethernet connection???  I had to reset the Modem/router just to get service back.

The plan is to have one Airport in the basement then connect a second one and put that on the second floor and if need be a third in between or have one outside during the summer.

Are these hair brained ideas possible with the hardware that I have

thanks