Use master version directly via:
python3 -m pip install --force-reinstall https://github.com/yt-dlp/yt-dlp/archive/master.tar.gz
yt-dlp xx
https://github.com/ytdl-org/youtube-dl
$ youtube-dl https://www.youtube.com/watch?v=36GT2zI8lVA
Use -F option to list the available formats for the video.
$> youtube-dl -F https://www.youtube.com/watch\?v\=36GT2zI8lVA
[youtube] 36GT2zI8lVA: Downloading webpage
[info] Available formats for 36GT2zI8lVA:
format code extension resolution note
249 webm audio only tiny 50k , webm_dash container, opus @ 50k (48000Hz), 2.74MiB
250 webm audio only tiny 67k , webm_dash container, opus @ 67k (48000Hz), 3.63MiB
140 m4a audio only tiny 95k , m4a_dash container, mp4a.40.2@ 95k (44100Hz), 5.13MiB
251 webm audio only tiny 99k , webm_dash container, opus @ 99k (48000Hz), 5.35MiB
160 mp4 192x144 144p 43k , mp4_dash container, avc1.4d400c@ 43k, 30fps, video only, 2.35MiB
278 webm 192x144 144p 71k , webm_dash container, vp9@ 71k, 30fps, video only, 3.86MiB
133 mp4 320x240 240p 82k , mp4_dash container, avc1.4d400d@ 82k, 30fps, video only, 4.44MiB
242 webm 320x240 240p 144k , webm_dash container, vp9@ 144k, 30fps, video only, 7.78MiB
18 mp4 320x240 240p 333k , avc1.42001E, 30fps, mp4a.40.2 (44100Hz), 18.00MiB (best)
Pick one of the listed format code and use it to download just the specific video format.
$> youtube-dl -f 18 https://www.youtube.com/watch\?v\=36GT2zI8lVA
[youtube] 36GT2zI8lVA: Downloading webpage
[download] Destination: Richard Feynman. Why.-36GT2zI8lVA.mp4
[download] 100% of 18.00MiB in 00:01