Fixes to the getting started documentation (#11154)

* Update get_started.md

-Streamlined python code
-Corrected outputs for example python code
-Corrected nonworking python example code

* Update get_started.md

Minor grammare fix

* Update beginner.md

Made explicit https calls

* Update get_started.md

Fixed something that might have failed the macOS test

* Keep the `dtypes`

This way it stays in sync with the upper part of the file.