If you’re looking into security. Make sure to run Ethernet to for corners of your sofets. Ethernet into your garage for either for a camera along with ap for iot garage opener. Even if the cameras you decide to running are wireless you can get a PoE adapter to convert to usb port to power the camera.
I would run drops to each corner of your house. One to your door bell. One to your garage. Also run a smurf tube to your outside of the house to your location of the drops.
man honestly if your asking this question, its going to be a lot to unpack for you. I would suggest you get one brand and use that one brand for this whole project. The tp link deco is a good product an allows you to manage all the ap’s for this on a central location. I would go this route as its more user friendly and easier for you. I would not use another routers or aps. Just please stick with one brand that works together.
You have NAT nightmare here… Like others have said you need to use those routers as access points. Your isp router will dish our DHCP for all of your devices and wireless clients. Also on top of that you will have to make sure your wireless channels aren’t the same as others.
My guess this did something like this from there root’d phone.
Mikrotik or ubiquiti