You cannot prepare enough for anything.
You can sightread better if you know your scales and arpeggios.
Taking drugs to overcome nerves is the thin edge of the wedge going in there.
Being unprepared heightens nerves.
They are all different and I find it hard to tell what flute suits me best.
By the time I got to the Paris Conservatoire I was very good at the scales and arpeggios.