As has been stated, you might have considerable difficulty in getting credit if you're not on the electoral roll. (If you're 18 or over, it's a criminal offence not to register. Annual registration forms have recently been posted out so, if your father knew that you'd be moving in, he should have included you on his form).
Once you've got that sorted out, you still need to find a company which will give you some initial credit, so that you can build up a good record. Capital One have a good reputation when it comes to giving a credit card to people with a poor (or non-existent) credit history. Their interest rates can be rather higher than with some other cards but you can start with Capital One, build up a good record, and then move on elsewhere:
http://www.capitalone.co.uk
Chris