Bash: Python3: command not found (Windows, discord.py)

On Windows the normal name for the python executable is python.exe (console program) or pythonw.exe (for GUI programs).

The python executable is sometimes called python3 on some platforms, where the default (python) is the old python 2. On many UNIX-based (inc. Linux and OS X) systems, python 2 is used by system utilities, changing it could have bad consequences on those platforms, hence the name "python3".

On Windows you should be fine - there are other issues on Windows but you won't get those unless you try to use more than one python version.

In the python installed("c:\\Installationpath\Python3.6.0") path you will find "python.exe", just copy paste in the same place and rename it as "python3.exe", now in the command prompt you can check python3 command should display your python installation. Don't forget to open a new terminal.