Hello Jilladler, how are you?
Welcome to the Microsoft Community!
My name is Paloma B., I'm an independent advisor, I'm here to help you in the best possible way.
I fully understand that you would like to turn your All In One computer into a Monitor for your computer.
Unfortunately this is not possible because a computer of this format, it is like a laptop, where the image comes directly from the video card with specific cables, that is, it does not have a configuration or way to disable and configure it to use it as just a monitor.
Usually it even has an HDMI or VGA port, but it is only for image output and not input.
I'm really sorry for that, but it is not possible to perform this configuration on an All In One computer.
I await news.
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