It is difficult to create an embroidery file (such as TAJIMA DST format) from a raster (bitmap) PNG picture with just any random graphics editor. This is because embroidery files are special vector-based images with additional instructions for the stitching machine.
However, an experienced graphics designer might be able to create embroidery design from some bitmap image, which can be done with usually expensive digitizer software. Some embroidery software can also possess basic digitizing function that can convert raster images to embroidery, but that's usually far from perfect. In any case, this is pretty much the only way to achieve png to dst conversion.