Blender is the big boy on the block in the open source 3D world. It has been used in TV and Film, notably a whole number of shots for “Man In The High Castle.” It’s a fully functional package that lets you go from concept to movie.
With that capability comes a learning curve. Fortunately, this learning curve is set to get much easier with the release of version 2.8, which is proving to be much easier for new users to grasp. The software does almost everything that commercial packages can do, and there is a huge community willing to help you learn.
You can grab the latest versions here: www.blender.org