You can stream videos directly from Youtube and many other video websites
Put yt-dlp.exe in the MPC-HC installation folder.
Then you can open website URLs in the player: Menu > File > Open File/URL
You can even download those videos: Menu > File > Save a copy
Tip: to be able to download in best quality with yt-dlp/youtube-dl, it is recommended to also put ffmpeg.exe in the MPC-HC folder.