CNC panels are made from 5mm white opaque Perspex. Then sprayed grey. Once dry, I use the CNC machine with an engraving tip to remove the paint and etch into the Perspex. This way the panel can be backlit and lights up when dark. Others use a laser engraver to create the text.
Another really cheap way to produce professional back lit panels is with a vinyl cutter available from amazon for around $150. Simply feed the vinyl into the printer and it will cut all the text out and shapes as required.