Using a laptop as a second monitor by using a cable

I'd like to know how can I use a laptop (windows 7) as a second monitor by connecting it with a cable to another laptop (windows 10). I want to use a cable, not wifi stuff like spacedesk, zonescreen etc.

My question is not a duplicate of the other ones because here I'm not just asking if it is possible to use only a cable, I'm asking a solution based on a cable.

Unless you have one of the extremely rare devices which have a HDMI input you will need a HDMI capture device. These convert the incoming data to USB or PCI Express. If your video bandwidth needs are modest, like 1920x1080 @ 60Hz then even the cheapest (25 USD or less) devices of this kind will work for you. These look like a slightly bigger USB stick with a HDMI female on the opposite end from the USB connector. The more sophisticated versions for 100-200-more is likely not worth it for your use case.

For 4K, you need Thunderbolt. Prepare for a major price shock, however: these are professional devices for movie studios and such. Even the cheapest device I am aware of is about a thousand dollars and then the price goes up. And up.

Well, most of laptops using LVDS interface on display. If old Win7 laptop won't be used anymore and you Ok to disassemble laptop and use only its screen, then you can buy (not so crazy expensive) LVDS-to-HDMI adapter, plus HDMI cable to hook up to another laptop and use it as a second screen.