well everyone in the country needs;
Power,
housing,
transport,
water;
and to all intents and purposes an internet connection.
so I’d say that’s a good list to start with in terms of bringing things back into the public ownership.
Id say as a bare minimum things where effective competition is impossible, so rail and public transport, water housing and to an extent power.
I wouldn’t worry about where to stop as it hasn’t even started yet!