I use Sketchup to design everything I build for woodworking. What file type do I export out of Sketchup and what software do I use to create the Gcode for the LongMill?
SketchUp can do the 3D design, but I don’t think it can do the CAM portion.
I think you can import an SKP file in to Fusion 360 and do the toolpaths from there and export the gcode.
@clark77494 Sketchup will export .dxf files and pretty much any of the CAD/CAM programs talked about here will import them.
I too like SketchUp for woodworking designs. There is a SketchUp plugIn called SketchuCam. Not super robust but may fulfill your wood working needs.