Hi and a warm welcome to the forum.
You have had some good advice above and I don't want to give you information overload, so won't go on too much
Why a week, I would say try a couple of weekends first, throw in an extra day as well. Turn up Friday dinner and stay until Sunday. Go local, then you can keep nipping home if you forgot something etc etc.
For a basic couple of nights you will get by with the car, we did a week a few years back with a family of four and just a Ford Focus

(think we might have had a roof rack with a couple of chairs tied on top

.
My BIL was on about giving it a try and I plan to take an extra tent for a weekend and let all 4 of them try that out soon. Do you know anybody who would let you borrow there tent.
As for the Hook-Up, I'm also a sparky and my lead is home made, I also have a couple of 4gang extension leads running to the sleep pods from the main one. I've never had a problem, that said I plan to buy a proper Hook-Up this winter and try and set a good example
Once your into camping and you know where your at with it, there's no looking back mate.
The first thing, if you are serious about giving it a go is looking at what sort of tent best suites you and what budget you have for spending on a tent.