If you have a silvercrest SL65, that will get the free channels on any satellite:
1) All Sky free to air from Astra2, a 45cm minidish will suffice for most of England, however 60cm is needed for far north/ Scotland.
2) All FTA on Astra1, including cnbc (for Tonight and Late Night shows). dish as above.
3) All FTA from Hotbird, including Bloomberg english version, but slightly bigger dish advised to get all channels properly, at least 60cm.
For other satellites, then a 60 cm dish size upwards .......
Note this assumes using the correct satellite cable, there's an issue with the latest Lidl kits in that the wrong cable type - rg59 - was included!
Obviously, the dish can only point at one satellite, if you want to get several, then it's either multiple lnbs, or a motor ......