It is a Juniper.
Not trying to be flip, but without information about its origin, or a name tag, the gods only know which of the dozens of juniper species, hybrids, or idiosyncratic horticultural cultivars of juniper this is.
First, which of the continents was this tree found on?
Come from a plant nursery?
Found in the wild? I mean someplace no human has ever planted junipers. Here the location really helps in identifying the species.
Found as a volunteer seedling as in your garden?
The juniper is showing a mix of scale and needle foliage. Many of the Juniperus chinensis junipers will do this. Some will only do it as a stress response, like shimpaku juniper. Some junipers pretty much always have a mix of foliage types - like San Jose Juniper.
The good news is that all junipers are treated more or less the same horticulturally, and for bonsai purposes pretty much all the junipers will work as bonsai.
Some of the North American native junipers are a little more difficult to work with than the Japanese and Chinese juniper species. But by and large assume this juniper is a cultivar or a naturalized seedling of Juniperus chinensis. It does resemble one of the J. chinensis varieties. But it could be anything.