The Part Design workbench is really powerful. And you can add a linear pattern to duplicate a feature in a straight line, or a polar pattern to duplicate it in a circle, or a multitransform pattern to combine several of these. You can create 'datum planes' in space to allow you to create sketches on planes that don't actually exist as either base planes or surfaces in the part. You can also add or remove material by creating another sketch on one of the base planes and adding a new pad or pocket, or by revolving a sketch around a construction line. Once you're done, select some edges that you want to tidy up and either fillet or chamfer them, and the part is done. Constrain it using the constrains, pad it into a solid shape of a given width, then click on a surface on the solid and create a sketch on that surface, again draw the sketch and constrain it, and then you can either create a pad out of that surface, or a pocket into it, and so on.

Set workbench to 'Part Design', create a 'body', create a 'sketch' on one of the xy,xz,yz planes, and then draw rectangles, circles, line segments, arcs, b-splines, etc. The 'Part Design' workflow is best, in my opinion. How did you try to learn FreeCAD? It took me quite a few tries to get the hang of it, but it is super powerful once it starts to click. I find FreeCAD and OpenSCAD to be good for different things but definitely prefer FreeCAD overall.

Freecad cnc