Satellite wired connection

Hi,

I have ordered the Orbi WiFi 6 mesh system, arrives tomorrow.

I'm wondering the best way for installing.

House is an large old farmhouse with thick sold brick walls, distance from home office (where router is located) to various rooms, is around 130 foot, whole house is on two floors, around 6,500 sq foot.

From the office, I have a single Cat6 cable running from the router to a hub other side of the house, with ethernet points in every room in the house going back to this hub.

I currently use the Netgear Nighthawk system, with them connected to the various hubs, which strangely, worked fine until a couple of years ago, now they need restarting (even resetting) a lot to get back working, but appreciate they are older tech now.

So question is, how would I make best use of the Orbi WiFi 6, given I have wired ethernet ports throughout the house, can I use the wired connection back to the router, instead of wireless?

Should the Orbi router be connected next to my main router, or other side of the house?

Thanks!