Welcome to the community!
Provided the tablet is a UK model running the stock Lenovo firmware, there should be no issue running Sky Go.
As you rightly surmise, Sky Go requires a WiFi signal for live viewing but if you subscribe to Sky Go Extra (£5 per month or free if you have multiscreen) you can also download content to for viewing offline when you have no signal.
Edit: Just to add, there is a possibility that that tablet may suffer from stuttering video since it is based on the Intel Atom chipset. The Sky team have fixed the issue on some devices, but others still have the issue but Sky are still working on it.