To receive TV programmes via a satellite dish you need:
EITHER a TV set with a Freesat tuner built into it (instead of the Freeview one which is fitted inside the vast majority of sets)
OR a satellite receiver set-top box (to use with a 'normal' TV).
A GENERIC satellite receiver box can receive all of the channels listed here:
https://en.wikipedia.org/wiki/List_of_free-to-air_channels_at_28%C2%B0E
A SKY BOX without a subscription acts becomes a generic satellite receiver.
A FREESAT box is actually configured to receive just a SUBSET of the channels from my link (although the other channels can be accessed through manually tuning them). The only feature that it adds in is its own electronic programme guide.
The foregoing statements ignore recording facilities though. A Sky box without a subscription loses the ability to record programmes. Generic satellite receivers tend not to incorporate recording facilities, whereas many (most?) Freesat boxes now do.