Try Freecad. I do all my CAD on it. Do some of the lessons first. Bit quirky but you get used to it. Files happily go through a slicer and into a Prusa 3d printer. It has some FEA. I think the founder originally helped develop Solidworks, and their eventual goal is an all in one system porting direct to multi axis machines.
Then there is SALOME, free and French - viva la France. Used to design nuclear reactors amongst other things. And it doesn't have an 'undo' option!! OPEN CASCADE
The world of open source programs is amazing. There is talk of making package downloading uniform between linux flavours to make it more like downloading a windows exe.

