step to cad conversion can possibly mean many things, including generic query about export of ISO STEP 3D files to 2D 'CAD' design. In this case it would be best to specify which CAD format you need and look for software tools based on that.
As for actual .cad files, these are used in several tools, but it's always unique format, meaning you need particular software to work with these.
Updated: September 18, 2023