Can Blender be used for business purposes? Can the free version of Blender be added to a new software by incorporating all the dev tools of it into this new software and then be given away for installation to the common public? Any way how that can be done legally for business?
Blender is GPL licensed - and subject to all the terms of GPL licensing (barring some components of it).  For more information, look here: https://www.blender.org/about/license/