If there is an adequate aerial connected to the Aerial/RF IN socket of the Sky receiver then signals from this will be passed through the RF OUT connected to the TV in the bedroom (as well as whatever the Sky box is tuned to).
If there is no aerial connected to the Sky box then all that will be seen is what the Sky box is tuned to
If what you want is Freeview through the TVs own tuner then an aerial *must* be used, either as described above or with it's own separate aerial