As someone who learned CAD on autodesk (inventor) ages ago, the only free modeling software I could grasp after working for a few hours was Onshape. Usability seems to be a real problem in this space, Freecad for example seemed to have a billion ways to do the same thing, but in the end only one of them was the real way, some tutorials leaving me with a model that doesn't conform. Awesome work! It seems like a hard p…
I pretty much only use the Part Design, Sketcher and Spreadsheet workbenches. Those mostly work OK together. I don’t dare branch out because of poor interoperability between benches; I sometimes use the Part bench as well but it’s so fiddly because you had to take it through two internal format changes to make it work in Part Design.
Hoping that one of the many open source CAD projects can supplant it eventually.