At the moment there is a bit of controversy around the matter of Fusion and "free".There are lots of different CAD programs out there and if you like the idea of producing Gcode with very little effort from artistic stuff,F-Engrave will do the job from a bitmap.Not really a CAD program but you will have something to look at.You might also have a play with Camotics as it will run a simulation of the code and its always good to see what you might be cutting before pressing the green button.For fairly basic 2D CAD you might have a play with LibreCAD and it exports dxf files,which most systems will cope with .