Hi, a while back I got two Google wifi to provide the wifi for my house. But I don't think I've set it up the best way.

Currently it's plugged into one of the ports on the modem/router combo and down the other end of the house... But I'm basically putting a router inside a router? Do I need to turn the firewall off on the ISP router? Or put the Google wifi in the DMZ? I can turn off the ISP access point and make sure everything goes through the Google wifi?

I've been having problems gaming with my friends on ps4, and connecting to the server on far cry 5. I'm wondering if the double router set up is causing problems