Assuming the computer/NVR has an HDMI output (ideally HDMI 2.0, although older HDMI versions work too), it can use a modern TV just like a monitor. I recommend a 43 inch model, as 43 inch 4K has about 100 pixels per inch, the same density as typical computer monitors.
It is mostly the same as just having a large monitor, but there are a few things to pay attention to, since you asked:
* TVs these days don't just show a video source. They have their own operating system, menus, advertisements, update notifications, etc. This can be a bit of a nuisance.
* Some TVs come with dumb default image settings that are bad on a PC desktop, like an overly strong sharpness setting, overscan, or dynamic contrast.
* You often get "limited" dynamic range (16-235) by default with a computer graphics card, and must manually increase that to full dynamic range (0-255) or else everything looks worse.
* The large panels they use in TVs often have a different pixel structure than most computer monitors. This makes text slightly less legible, although most people do not notice.
* Some TVs have higher input lag if their "game mode" is not enabled.
* Don't use HDR mode in Windows unless you are specifically using HDR apps/games.
When it comes to picking a brand for a cheap 43 inch 4K, I've tried TCL, LG, and Samsung. Samsung had the best image quality by far, and the fewest settings tweaks required to make it look its best.