You need to talk in the first instance to the electricity supply company who runs the network in your region. This is the same company (or its successor) that used to SUPPLY the electricity before the market was opened to competition - because they still run the distribution network. They will have a new installations department, and you ask them for a quote. That results in a surveyor coming out to assess the actual job.
They almost certainly will subcontract the work to someone else, but you have to go through them.
If they have to dig up the road or put a new rural pole up, they will work that out, and provide you a connection to the boundary of the highway and your land. You may want it further than that (into your plot).
They will explain the standard required for a housing required to put the meter in, but probably don't do this bit themselves, Anything after the meter is your job to work out - via a contract with an electrician who can install you a few sockets inside the same housing.
Impossible to guess how much as it depends on distances, but probably from �1500.