There are so many programs to choose from. As Monk said do a Google search. There are even plenty of free ones. If you don't have the Adobe suite or Corel, just use Microsoft Word. It will do all resizing and importing you will need for practicing.
I use an NSK Emax EVOlution. Kind of expensive, but does a great job. I've only been engraving for about 6 or 7 years and I'm not a jeweler and I've never worked ewithnamel but I cannot imagine needing a flex-shaft.
I had to miss this years FEGA because I was pretty sick. My wife says she would rather I didn't go this year unless there is a proven vaccine by then and things are back to somewhat normal. Looks doubtful.
"Always tell the truth. Then you don't have to remember anything." ~...