I am about to buy the Deco XE75 Pro.

We have just had full fibre to the property installed and I intend to connect the Deco directly into the Openreach box on my study wall with an ethernet cable (I hope I am right that I can do that)

Reading the manual online for the XE 75, it refers to setting up the wifi network and separately to setting up the 6Ghz wifi network. 

Is it recommended to give those the same SSID and password or different ones ?

If the answer is "different", when I subsequently make a device (e.g. iPad) join the network, which network should I tell it to join ? 

And why ?

(I have to date had a Linksys tri-band mesh connected to a Virgin hub - this worked well; it had only one SSID and devices moved seamlessly from node to node as the devices were moved around the house. This is an experience which I would want to replicate)

Thank you very much for your advice