You need to apply for a provisional licence, which gives you permission to be on the roads while you are learning.
While you are learning you cannot drive the car on your own, a driver older than 21 who passed their test more than three years ago must be with you.
While you are learning with a provisional licence you must also display L plates on the car, but they must be taken off if a qualified driver is using the car.
When you think you're ready to drive on the road you need to take a test, which is in two stages.
A theory test is first, and is taken on a computer, lasting 40 minutes and is 35 multiple choice questions.
Once you pass that you have two years to take and pass a practical test with a driving examiner, and then you can drive legally.