Ecole 42's pool, what to expect and how to prepare?

I have gotten accepted into the pool for ecole42. Does anyone have experience there, or know somebody that does? The one I will be attending is in Paris. I have just started FreeCodeCamp because I want to be ahead and be able to excel when I get there. I also know that the pool is extremely rigorous and I want to have a better chance of passing and getting into the school full-time. Basically, I am just looking for advice for Freecodecamp as well as ecole 42 paris or USA.