Once you have Ollama installed and running, you should be able to load a model and run a test query via Powershell. You will also need to download any new models via Powershell, as well as check any default parameters, template, or system prompt information in Powershell, as none of that has been built into this document (this is mostly intended as a tutorial and things are getting complicated enough).
This also does not automatically pull models, you will have to edit the “Text Only” and “Vision” models yourself.
With the environment variables set, the last check is to confirm that Wolfram Mathematica is allowed to access the Internet (Edit -> Preferences -> Internet & Mail tab).
If that all works, run the three-part “Run Once” section, scroll down to the bottom, enter a User Prompt, confirm the model and other settings are correct, and click “Submit”.