Having had a look at your new router I would use an ethernet cable from your netgear to the blue wan port on the TP Link. Connect a PC / Laptop. with ethernet cable to one of the yellow lan ports. This will allow you to set up the tp link as needed. The cable can be removed once set up is complete.
Connect, by wi fi, to the tp link, just to ensure it is working.
Open your Netgear router settings and turn wi fi off
(You could leave the netgear wi fi on for downstairs and connect the tp link to the powerline adapter upstairs so you have two wi fi networks in the house)