I want to get softwar freely. How it ?
The place to ask would be in the Illustrator forum (you've posted in InDesign), but I suspect the answer is that there is no free converter.
Converting an Ai file to DST or any other machine embroidery format isn’t simple as you think.
It’s not just like converting JPEG to PNG or any other. Instead of that it requires manual digitizing process which takes time + effort + techniques.
If you want to do it yourself then you have to get:
1. Embroidery digitizing software (like wilcom or pulse which are expensive)
2. Essential skill of machine embroidery digitizing (takes time to learn)
and then you will be able to convert a picture to DST format. Mostly I use these guys https://zeedigitizing.com for my embroidery need. May help
my digitized horse photo