If you are going to keep wild boar you'll need a dangerous animal licence - a quick google will tell you all you need to know
I looked a while back, but think I must've forgotten it all ! I know you need REALLY SECURE fencing and all sorts of red tape and legislation - I was quite quickly put off just by that ! I think it was Hilary's mum who said they're fairly 'bitey' and very good at escaping.
IF, you're going to go for it, I'd suggest fattening and slaughtering a couple first, just to give you a chance to see how they are to handle and what they actually taste like. Just trying to be the voice of reason lol!