how do you convert a .png to a .tap file?

how do you convert a .png to a .tap file? many thanks

It's not a sensible question, png is a graphics file, tap is a gcode file, there are many ways to process a png to end up with a tap file.
The best way is to describe what you are trying to achieve.

As Eddy says, you need to convert the png to a dxf file (using CAD or Inkscape etc) then export it to a CAM program which then creates the .tap file....