meh...
Capturing what's on your screen is easy -- use the PrintScreen key or Windows Snipping tool. What's hard is capturing 30-60 [or more] frames per second [fps]. Each snapshot is a lot of data -- more than can be written to a hard drive unless you have special equipment or hardware. The solution is video encoding, which compresses the amount of data to something more manageable. And that's where it gets complicated... The more data you save, the truer the image, the larger the file. More advanced encoding is more efficient -- saves more quality in relatively less disk space -- but tends to be processing intensive and slow. If you want to edit that video it adds more complications -- the best methods of video compression [CODECs] when it comes to editing tend to create huge files, because they save more data for higher quality, and are mostly too slow for capturing.
Special hardware, e.g. add-on capture cards or boxes can make it loads easier to capture quality video. Using your device's GPU *may* help, but bear in mind that often the video you want to capture is already using the GPU to display that video, whether a movie or a game, so using it for encoding may not work so well, or even be possible.
If you don't use capture hardware, capturing the best video means testing encoder & video settings to arrive at the best compromise, writing the most data that your hard drive(s) can manage fast enough to achieve your target fps. It depends on hard drive write speed; how fast your PC can get that data to the hard drive; how much horsepower you have available, after displaying whatever you want to capture, to compress the video; and finally, how efficient the encoder is, since that helps determine how much horsepower you'll need.
Apps like OBS Studio, Ashampoo Snap etc. help with coming up with and using the best compromise for your system, letting you choose the codec [encoder] used etc.
obsproject[.]com/
videohelp[.]com/software/Open-Broadcaster-Software
ashampoo[.]com/en/usd/pin/2424/multimedia-software/snap-12
videohelp[.]com/software/sections/codecs
Or you can use something like RecMaster Pro, which takes way most of your choices, making it hard [if it's indeed possible] to get the best recording your PC is capable of. Installing it doesn't have too much impact on Windows -- you have the program's folder plus a new folder in Users\ [UserName]\ AppData\ Roaming\, while the registry gets 2 new keys, one for uninstall.