Juniperus procomben "nana"
Yup
Not a bad starter really. Chances are it is deprived of Sunlight and you would want it in a bright space outdoors until you
can adjust it to full Sunlight over time, maybe a month... There it will do best, Full Sun!
Do not water until it needs water, but never dried out. Best way is to go ahead and work the top rocks loose carefully
and remove the moss, then replace the pebbles on top. Order some inorganic bonsai soil,
(I like
https://www.bonsaijack.com, very clean, friendly, helpful and fast).
Check for spider mites by holding the new acquisition over a piece of white paper and tap the foliage a few times.
Study all debris on the paper for tiny bugs moving about. Personally I would get (for a handful of small bonsai or less)
a premixed "Safe Soap" in spray bottle and wet the foliage with it after foliage dries from watering.
I do this as a preventative, but if I see evidence I use Malathion on all my plants. Neem oil works good too.
DO NOT PRUNE IT. DO NOT REMOVE THE GROWTH TIPS this year. When it recovers from repotting, prune the following year.
The growth tips or runners collect Sunlight best for energy. They are the work horses. You need them.