FreeCAD is a free open source 3D parametric modeller, allowing you to design real life 3D objects. You can follow at:
It's available for Linux, Mac and Windows from the official site at https://www.freecadweb.org
It can be used for all kinds of 3D design tasks such as 3D printing, technical drawing, architecture etc.
Georges-Émile Carette, La Cour Lacordaire, Au Couvent Des Carmes, Rue De Vaugirard (1911)