Some companies who operate driving crash courses offer a guaranteed pass. No one can guarantee you will pass your driving test and beware of any organisation that offers a "guaranteed pass" . Look at the small print and see for yourself the conditions that apply. You will find that the "guaranteed pass" is probably an offer to pay for another practical test and a couple of hours shared tuition before the test at a date and time to suit the school. You will probably be responsible for any accommodation charges and of course your travel costs. There will also probably be either a time limit in which you must pass, or a limit on the number of attempts that they will pay for. So give some thought about what a "guaranteed pass" is really worth and whether you would be better off having quality one to one tuition with the benefit of all your tuition time being spent behind the wheel.
A driving crash course is an excellent way of passing your test in the shortest possible time but no one can guarantee that you will pass. If we could we would be millionaires