Ive got my level 1, which is very easy and I dont think anyone ever really fails so if you have any experience with football at all Id say go and do this as soon as you can as then you are obviously able to coach and gain experience, my level one was just a 1 week course by the way.
Level 2 I think is a little bit more challenging but dont hold me to that as I havent gone for it yet. But Ive saw that it is recomended you get a bit more experience coaching before you go for the level 2