Józef Nowakowski was a contemporary of Chopin, and his music reflects the Polish salon style of the mid-19th century. This piece is characterized by melodic grace and idiomatic piano figurations common to the period.
Ensure the clarity of the ornamental runs, which should be played with an elegant, light touch.
Comparable difficulty and character — good candidates for what to learn next.
Ballade No.1 (Op.34) is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8.
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.
Ballade No.1 (Op.34) 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 Ballade No.2 by Józef Nowakowski, Ballade by Józef Nowakowski, Waltz No. 2 by Dmitri Shostakovich — see the full similar-pieces list on this page.