Everyone i've known thats driven outside of lessons has had their own car (Dave and jenko), so might be cheaper to get your own insurance policy rather than being on your dads? Like a girl I work with, she passed her test not long ago (after failing it about 4 times) and she shares a car with her mum, they found it cheaper for her to be the main driver and her mum to be the 2nd because her mum hadn't driven for a few years...