You need to use https://github.com/smurfix/buildscad https://github.com/smurfix/buildscad which can convert OpenSCAD to Build123d, then you can export a STEP fi

You need to use https://github.com/smurfix/buildscad https://github.com/smurfix/buildscad which can convert OpenSCAD to Build123d, then you can export a STEP file. It has a few limitations, but for simple OpenSCAD files it can generate an equivalent representation in OpenCASCADE.