Disconnecting sky - what to do now?

Hi to all you wonderful tech savvy people (of which I am not onw).  I have disconnected sky, 2017 Sony Bravia TV is saying - check aerial as not connected.  I have no idea if we have an aerial on the roof.  My question is (1) do I use my Sky dish, even though I dont have sky and if so what do I need to do.  (2) if I cannot see an aerial on the top of the house - what do I do then. Thanks heaps :)