For youtube, the best option on the internet is yt-dlp. It's a command line tool and has a learning curve, so if ease of use is your priority, it is not for you.
But if you want the absolute best quality and fastest download speed, then you got to try it once. Just download yt-dlp, download ffmpeg, extract ffmpeg and put yt-dlp in the same folder. Then go to the address bar of that folder, type 'CMD' and hit enter. In CMD window that opens, type this : yt-dlp [youtube URL]
Copy paste that url without the brackets. Hit enter. That's it. It will download the best quality Youtube server has. If you want options like different resolutions or convert into something else, find them here:
https://github.com/yt-dlp/yt-dlp
Again, if you want ease of use, this is not for you. Try FDM or JD maybe, they are more like IDM.