As previous speakers have already confirmed, this is PRINCIPALLY possible. I also use this at home in my rented flat (3rd floor) to establish the connection to the basement. However, the performance is largely dependent on the local conditions and can vary greatly from building to building.

That is the idea behind the device.
I also recommend connecting central devices such as a NAS or the router directly to the device, otherwise a lot of bandwidth is lost.

In principle, yes