Package installation with pip in python 3.6 can be done through following steps:

1. Open command prompt (cmd) [start–>cmd]
2. Type pip install

Make sure system is connected to internet.
If you are connected to Internet through proxy [login username and password required], follow these steps:

1. Open command prompt (cmd) [start–>cmd]
2. Set the proxy settings by typing following commands:
   set HTTP_PROXY=http://domain\username:password@proxyAddress:port
   set HTTP_PROXY=https://domain\username:password@proxyAddress:port
3. Type pip install <package name>
   Ex: pip install numpy;

Fig: Installing python packages with pip