These are short, virtuosic insertions designed for concertos. They exemplify Beethoven's demanding approach to improvisation and structural cohesion within a small format.
The main technical challenge lies in the rapid scale passages and the need for stylistic alignment with the concerto's character.
Comparable difficulty and character — good candidates for what to learn next.
2 Cadenzas for Piano (WoO 58) is rated Henle level 7 of 9 — late advanced repertoire, roughly ABRSM grade 8 and above. In the RCM system it corresponds to about level 9.
You should be comfortable at Henle level 7 — meaning you can already play level 6–7 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 2 Cadenzas for Piano (WoO 58) lasts about 2 minutes.
2 Cadenzas for Piano (WoO 58) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include 13 Variations on 'Es war einmal ein alter Mann' by Ludwig van Beethoven, Piano Sonata No. 14 'Moonlight', No. 2 by Ludwig van Beethoven, Piano Sonata No. 8 'Pathétique' by Ludwig van Beethoven — see the full similar-pieces list on this page.