Scriabin's Preludes, Op. 11, are a remarkable set of character pieces, with one in each major and minor key. They showcase his evolving harmonic language, moving from Chopin-esque lyricism to his distinctive, more dissonant later style.
Develop a keen sense of harmonic color and the ability to navigate Scriabin's unique harmonic progressions.
24 Preludes (Op.11) is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 6 — meaning you can already play level 5–6 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 24 Preludes (Op.11) lasts about 30 minutes.
24 Preludes (Op.11) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.