How difficult is prelude in C Minor?
This beautiful prelude is amongst the easiest in the WTC (which is not to say that it is easy). You should be able to tackle it since I estimate it being around grade 6/7. The fugue is another matter altogether.
What grade is Bach prelude in C Minor?
Bach, Johann Sebastian - Prelude in C minor, BWV 999 (Grade 4, List A1)
Is prelude in C hard?
Known as a "beginner's piece", and indeed quite easy to learn, I think it is actually quite hard to play well (at least for one fairly new to playing piano). Interpretations also vary widely for this piece.