Question How do I change my modems network?

[ComputersAreHard]

https://imgur.com/a/GQX0V9T

View: https://imgur.com/a/GQX0V9T

Just drew my problem with MS Paint

Im trying make the Nova Modem change network to the one Fios Has

 

[ComputersAreHard]

The Fios and Nova 1 are on the first floor of my house.
The Nova 2 and the PC are on the second floor.

When I connect the nova ethernet to my PC it gives me the wrong network I want. It gives me the "RexyWifi" instead of my primary FIOS One which is "RexyEthernet"

 

[Ralston18]

What is the end objective?

What do you expect to gain by changing from a wired network connection to a wireless connection with another "router" added to the network?

Who has full admin rights to the router(s)?

Late Edit:

Please update your post to include make and model information for all devices in your sketch.

 

[ComputersAreHard]

The Wifi Network "RexyWifi" is set by the Nova MW6 Wifi and it does not perform well. I get 30Mbs download and 27 Upload.
However when connecting straight to the wifi network created by the Fios Router [G3100] "RexyEthernet" I get about 300mbs and 175mbs Upload.
I want to make the wireless connection a wired connection so it can connect to the Fios Router [G3100] and get more mbs.
However the Nova MW6 Wifi Extender only lets me connect to the "Rexy Wifi" instead of the "RexyEthernet" when making a wired connection from the Nova to the Ethernet port on my computer.