Hi Harley Roberts,
Thank you for posting in Q&A forum.
Generally speaking, the HDMI port of a laptop is used to output data and does not support input data function, so it cannot be connected to the host as a display. Its display can only be used as a dedicated machine. If you want to set up your laptop as a spare second display, you can use the built-in Windows function to do this wirelessly.
Disclaimer: The above mentioned links are not from Microsoft's official website. The information provided on these pages is relatively accurate and reliable. However, you should be aware that these pages may contain product advertisements that you may not need, so please read them carefully and confirm that they are what you need before downloading and installing these advertising products.
I hope the information above is helpful.
Best regards
Zunhui
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