Bach's six preludes are concise contrapuntal pieces, often serving as introductions to more complex works or as standalone studies in musical ideas. They are exemplary for their clarity of voice leading and harmonic logic.
Focus on differentiating the independent melodic lines and maintaining rhythmic precision.
6 Kleine Präludien is rated Henle level 2 of 9 — beginner repertoire, roughly ABRSM grades 2–3. In the RCM system it corresponds to about level 3.
You should be comfortable at Henle level 2 — meaning you can already play level 1–2 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of 6 Kleine Präludien lasts about 8 minutes.
6 Kleine Präludien is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.