"Python not found but can be installed from the Microsoft store"

Question

I'm trying to start learning Spark, so I am following this Udemy guide to set up a development environment. Some notable differences from the guide is that I already had Python 3.7 installed, so I am using that instead of Python 2.7, and I installed Spark 3.1.2 rather than Spark 1.6.3 like in the guide.

When I try using pyspark to run the simple example from the guide sc.textFile("C:\\deckofcards.txt").first(), I get the error Python was not found but can be installed from the Microsoft Store. I believe that Spark 3.1.2 is compatible with Python 3.7, so I'm wondering why I'm getting this error? Python is added to my path

Also, this seems like an extremely laborious process to get Spark set up. Why can't I just use pip install pyspark? Also, why do I need to install JDK?

Thanks in advance for any help - I've been at this for nearly two hours!