I can definitely understand your confusion and frustration.
Let me say that you did the exact thing you should have done when confronted with a coding concept that you’re unfamiliar with: you Googled it. (everyone does that, and if they say they don’t, they’re fibbing 
)
Are you on a Mac or Windows? On a Mac the terminal is called, “Terminal”. It’s your C drive and file system. It just doesn’t have a fancy User Interface (UI) (like if you click on the “My Mac” icon on your desktop you can navigate through applications, downloads, files, etc). And, knowing some basic Unix commands helps when using the command line prompt in your terminal so you can navigate around, create files, directories, etc. (I see that he uses commands like pipenv and cd, etc. in the video).
Have you taken the command line course by any chance or ever poked around in the file system on your computer via Terminal? It might be worth looking into. If I recall correctly, it’s a short course.
I can see how the video would be confusing b/c he discusses having different versions of Python and different versions of Python libraries installed in different environments. (an aside–Python 2 is no longer supported and any company who uses it would, or, should have reconfigured their code over to Python 3 by now). And, through your research you would have read that like software is updated, Python libraries are updated from time to time (certain methods are deprecated, or, no longer used but replaced by something else).
Anyway…When you’re in the learning environment, doing lessons on the DS path, the py.script window—where you write and execute python commands–that’s exactly what you would use Jupyter Notebook for: writing and executing python commands and sharing your notebooks (code) with others. (there are code cells and markdown/text cells for notes.) You can also write and execute Python–like in the video–in a virtual environment using a text editor (there are tons of free text editors out there for Mac, Windows and Linux). In the video, I believe he’s using Visual Studio. https://www.lifewire.com/best-free-text-editors-4155819
Did you successfully download Jupyter and can you initiate it via typing in “jupyter notebook” in the terminal/command prompt window? Open a new Jupyter Notebook session and create a new file. Create some variables and print() them out:
It’s the same as if you’re typing in the script.py window in Codecademy.
You can also import any Python library—pandas, numpy, scipy, seaborn, etc. You have the option to do off-platform projects (import csv files, etc) on the DS path, I recommend doing it.
I hope I didn’t add to any confusion. If you have more questions, reach out to me. 
