Wireless to Ethernet signal conversion

I'm not sure if the topic title entirely makes sense but the idea is that I need to get a connection through a 3 storie structure.

On each floor, I have a cluster of servers set up. Conventionally, I would thread cat6 cables through the building but due to various reasons I cannot do that.

On the ground floor there are 2 ground lines which project a wireless signal.

I'm wondering, is there some way I can convert the wireless signal into an ethernet line? Perhaps through some kind of interfaced adapter. I've thought of buying a throwaway laptop and bridging the connections manually but I'd prefer to avoid that option if there are feasiable alternatives.