Connect the aerial to the receiver.
If you dont know what your local transmitter is, go to the Freeview website on your PC. Put your dad's postcode in and it will tell you. You will need this for ABM later.
In tuner configuration, you should see DVB-C and DVB-Tl.
DVB-C, set this to disabled, not configured, nothing connected.
DVB-T, set the country to UK. If you mast is listed select it. Otherwise "All regions" is fine.
In ABM:
Disable the Freesat provider.
Enable Freeview, select your mast/region and run it. i.e perfom an ABM scan. You don't need to run ABM regularly. If it is on a timer disable it.