Hello and welcome to Apple Support Communities, JonKM.
If I understand your post correctly, you're trying to access your Apple TV+ subscription on your Mac using the website. I’d like to help.
Follow the steps in this article to access Apple TV+ and other channels:
Download and stream shows and movies from Apple TV+ and Apple TV channels
"Download a show or movie
If you subscribe to Apple TV+ or an Apple TV channel, you can download TV shows and movies included with your subscription on your iPhone, iPad, iPod touch, and Mac.
- Open the Apple TV app on your iPhone, iPad, iPod touch, or Mac.
- Go to the channel's page. Or search for a movie or TV show.
- Tap or click the download button next to the TV show or movie".
Subscribe to Apple TV channels in the Apple TV app
Let us know if that resolves this issue for you.
Thanks for using the Apple Support Communities. Take care.