If it is not using the correct one because you have multiple Python versions installed, wherever the guide says py below, use the path to the Python version you want to use. For example, C:\Program Files\Python39\python.exe.
If it is not using the correct one because you have multiple Python versions installed, wherever the guide says py below, use the path to the Python version you want to use. For example, C:\Program Files\Python39\python.exe.