Can you use a laptop as a monitor?
The HDMI port (or VGA, or DVI, or DisplayPort) that comes on your laptop will only work for outputting its display and it will not work as a video input for another device.
However, you cannot connect your laptop to your PC with a cable to get your laptop to display what your PC is outputting.
How can I use my laptop as a monitor for HDMI Windows 10?
Windows 10, How to extend display using HDMI –
Can I use my laptop as a HDMI input?
If your laptop HDMI port is only labeled “HDMI” then it is output only. If it is labeled “HDMI-in” then it is an input. Each HDMI port can only be an input or an output, no switch hitters here. If your laptop does not have an 18.4 inch screen, then there is no chance that you have an HDMI-in.
How can I use my laptop as a monitor for HDMI?
Plug the monitor’s HDMI cable into a flat HDMI port on the right or left side of the laptop. Make sure the other end is plugged into the display. The cable is identical on both sides, so it does not matter which end you connect to the laptop or monitor.