This piece, also attributed to Mozart, is a delightful and simple exploration of a theme and its variations, characteristic of the Classical period's clarity and balance. It offers a light and charming musical experience.
Emphasis should be placed on achieving a pristine and articulate sound, particularly in the accompanying figures.
Andante variato (K.Anh.138) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 4.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 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 variato (K.Anh.138) lasts about 5 minutes.
Andante variato (K.Anh.138) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.