I got stuck on googling how to make a fillet in freecad, to which the answer appeared to be, "yeah, nah, you sort of can't". Oh okay, this program is not for me.
Edit: if people want to help/criticise, I recall the problem was that I couldn't do it parametrically, which is the only way I like to model any engineering parts. So far the only thing that information has gotten me is a downvote. If freecad is as full featured as you say, then this should be easy to do. Feel free to tell me how.
EDIT 2: after the info I got, I looked into it more and discovered my problem was a bit different - I couldn't do a parametric offset line in a sketch, because I needed to make a particular pattern. I ended up doing it with OpenSCAD if I recall. I apologise for saying freecad couldn't do fillets, that would've been extremely basic. It was still a very painful experience just to figure out that it couldn't do what I needed.