I have an office in the garden and I want my internet from the home to extend to that office (the home wifi won't reach that far).

I have bought and installed an EAP655-wall, which is wired via ethernet from the router/modem in the house. 

The EAP655 works, but creates a second network with a different SSID. Is it possible to change the SSID and password so that it's the same as the home Wifi? I think this is known as an extender or a mesh? It ould be more convenient that having to change networks each time I move from the office to the house.

Is it possible to do this with an EAP655-wall, or have I bought the wrong thing?

Thnaks on advance.