Please excuse my ignorance.
I recently purchased a new house around a month ago. I did not set up any electricity or gas connection but there still seems to be electricity. Presumably from the previous tenants/owners.
Do I simply call up my preferred provider and set up a new connection with them?
And what about the bill for the interim period before setting up my new connection under my name?
Yes.
You are meant to do this on day 1 of moving in and provide the meter readings to provider. Anything before than date/reading is not your liability.