Are there cables to connect a DVR to a tablet using HDMI?

It sounds like you're trying to connect your DVR to your tablet, which might be tricky. I can only find male USB Type-C to HDMI cables that allow you to mirror a phone's screen to a monitor, but not the other way around. You can also look for HDMI female to USB-C adapters, but the direct male to Type-C cable you're after might be hard to find.

You could try searching for a USB-C Female to HDMI Male Adapter on Amazon; that might help. However, be sure to check the comments specific to your situation to see if it meets your needs. Just a tip, many Type-C to HDMI cables aren’t bidirectional, meaning you may be limited in how they work.

Yes, there are indeed adapters and cables available, but keep in mind that for them to work, your tablet’s Type-C port needs to support video input. Most gaming Android tablets do have video output, so it might work for you, but it's something to double-check.

Unfortunately, I think connecting your DVR to your tablet might not be possible with what's available. The USB-C port on tablets typically handles video output and not input. Even though you can find USB-C to HDMI cables, they usually only work one way—from USB-C to a display, not the other way.