This extremely short and simple piece by Mozart, cataloged as K. 1a, is a very early composition likely intended for beginners. Its charm lies in its unpretentious simplicity.
Focus on developing a clean, even touch and precise note accuracy.
Andante in C major (K.1a) is rated Henle level 1 of 9 — beginner repertoire, roughly ABRSM grades 1–2. In the RCM system it corresponds to about level 1.
You should be comfortable at Henle level 1. 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 (K.1a) lasts about 1 minute.
Andante in C major (K.1a) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.