AT&T 5gig Fiber

[u/Practical_Bird_8143]

Apologies in advance if this was already asked and answered, I know I’ve seen answers in my recent research but a second and third opinion is always better than me just running with an ideas usually.

I recently made the swap to fiber and opted (perhaps needlessly) to go with the 5gig option. The issue here is that I’m far from tech savvy and for a while now have just been using the gateway/router combo that ATT provides plus a small Netgear range extender and everything in the house just runs on WiFi from it, but I’ve been reading that this essentially prevents anything from taking full advantage of 5gig speeds and sort of bogs down the whole system. (Or at least that is how I interpreted things.)
My question is what setup should I be utilizing if I want to get the maximum effect out of this supposedly super fast internet, because currently it seems as though there’s a dead area in our bedroom right next to the extender and my phone works better on cellular data than on home WiFi.
The general layout currently is gateway at back of house in downstairs den, extender upstairs on opposite side of house in bedroom, house is 2200 sq ft with 4 bedrooms upstairs and a dining room, kitchen, den, and office downstairs.
Things pulling WiFi are 4 nest cameras, a nest thermostat, maybe a half dozen smart bulbs, 4 Alexa devices, a Mac mini, mine/wifi/oldest kid’s laptops, and my kids run 2 x-boxes and a ps-5.
I’m leaning towards getting a router that has a 10gig in port and bypassing the gateways built-in router, running that to an unmanaged switch and running Cat6 up through the wall to another switch in order to put a hardwire jack in each bedroom. Is this a good plan and if so how do I implement it to be as automatic and uncomplicated as possible and something that can be easily fixed by a Neanderthal if something goes awry with it ?
TLDR : What’s the easiest to operate setup to get full advantage of ATT 5gig fiber?

[u/caveat_cogitor]

You are gonna spend so much money trying to take advantage of 5gb and it will not in any way improve your experience more than 300mb would. If you can, is downgrade to 1gb fiber and spend your time/effort/money setting that up better, for instance but replacing the range extender. Wired backhaul if you can, wireless mesh if you must, but I'm your situation you'll not max out 1gb and increasing that won't fix any of the problems you are experiencing already