Is it possible to use Blender's Python API scripting directly from Python IDE? If so, how?. I was looking forward to something that would allow me to help develop a game completely using python.
You can develop Blender Python add-ons from external IDE's easily, and without compiling Blender as a Python module. The often referenced method of compiling Blender as a Python module has long been defunct, and only works for certain OS's.
Most add-on developers work by opening a project in the
2.78/scripts/addons/ directory of their Blender installation. From here, you can develop directly in Blender's filesystem from your favorite IDE, then hit F8 in Blender to refresh/re-compile your add-on live.
See this post for a more detailed discussion: The Best Way to Develop Blender Python Add-ons
you should install blender as a python module
see this tutorial : https://wiki.blender.org/index.php/User:Ideasman42/BlenderAsPyModule