This early Andante by Mozart, K. 15ii, is a delightful example of his youthful compositional style. It features a graceful melody over a light, Alberti-bass accompaniment.
Practice evenness in the Alberti bass and bring out the melodic line with a clear, vocal quality.
Andante in B-flat (K.15ii) 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 B-flat (K.15ii) lasts about 1 minute.
Andante in B-flat (K.15ii) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.