You must pass your theory test before you can book your practical driving test.
The theory test consists of two modules:
Module 1 - 50 multiple choice questions with a pass mark of 43
Module 2 - A hazard perception test with a pass mark of 44 out of 75
You must pass both modules at the same time to acquire your theory test certificate.
Your certificate is then valid for two years.
If you have not passed your practical driving test within that two year period you will have to take your theory test again. Quality Drive can advise you on the relevant study aids needed for your Theory Test and will give you all necessary guidance.