Hans Christian Lumbye's '12 Dances' are known for their lighthearted and accessible character, typical of the popular dance music of the 19th century. They offer cheerful melodies and straightforward rhythms.
Focus on a flowing legato and a graceful waltz rhythm.
12 Dances 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 12 Dances lasts about 10 minutes.
12 Dances is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.