update windows docs

Author: eulertour

docs/source/installation/windows.rst

@@ -42,7 +42,7 @@ Make sure you can start pip using ``pip`` in your commandline. Then do
 ``pip install pyreadline`` for the ``readline`` package.
 
 Grab the pycairo wheel binary ``pycairo‑1.18.0‑cp37‑cp37m‑win32.whl`` from https://www.lfd.uci.edu/~gohlke/pythonlibs/#pycairo
-and install it via ``pip C:\absolute\path\to\the\whl\file``
+and install it via ``python -m pip install C:\absolute\path\to\the\whl\file``
 
 clone the manim repository if you have git ``git clone https://github.com/3b1b/manim`` or download the zip file from
 the repository page with ``Clone or download`` button and unzip it.
@@ -56,5 +56,5 @@ Test the installation
 
 Type in ``python -m manim -h`` and if nothing went wrong during the installtion process you should see the help text.
 
-Use ``python -m manim example_scene.py SquareToCircle -pl`` to render the example scene and the file should play after rendering. The movie file should be
+Use ``python -m manim example_scenes.py SquareToCircle -pl`` to render the example scene and the file should play after rendering. The movie file should be
 in ``media/videos/example_scenes/480p15``