Where the box should sit

The box goes between your broadband router and whatever provides your Wi-Fi.

If your Wi-Fi comes out of the router itself, the box provides the guest Wi-Fi instead, so it needs to sit where the customers are. In a back room or a locked office it will not reach them.

If you have separate access points around the building, the box sits between them and the router. Your access points keep doing the coverage exactly as they do now, and the box can live next to the router.

It needs a mains socket and one network cable. That is all.