Schubert's Andante in C major, D. 29, is an early, charming piece often presented as a theme and variations. It showcases his natural melodic gift with a sweet, song-like quality.
Work on maintaining a consistent legato line and shaping the melodic phrases with sensitive dynamics.
Andante in C major (D.29) is rated Henle level 3 of 9 — late beginner repertoire, roughly ABRSM grades 4–5. In the RCM system it corresponds to about level 4.
You should be comfortable at Henle level 3 — meaning you can already play level 2–3 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 Andante in C major (D.29) lasts about 3 minutes.
Andante in C major (D.29) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.