This is a charming salon piece by Brazilian composer Agérico Lins. It is distinctive for its characteristically Brazilian melodic grace and straightforward formal structure.
At Henle 4 this is an intermediate piece that expects secure technique and real attention to phrasing. The main demands: a true singing tone, with the melody floating above the accompaniment; a left hand with real melodic or rhythmic responsibility of its own; and precise articulation — the difference between crisp and blurred is the piece.
Focus on maintaining a smooth, singing melodic line against the accompanying figures.
Comparable difficulty and character — good candidates for what to learn next.
A level or two down with the same spirit — ideal if this piece is still out of reach.
Where this piece's skills lead: slightly harder works making similar technical demands.
Esperanto is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 4.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 Esperanto lasts about 3 minutes.
Esperanto 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 Arabesque No. 1 by Claude Debussy, Black Beauty by Duke Ellington, American Beauty by Joseph Francis Lamb — see the full similar-pieces list on this page.