Earlier quoted context omitted.
Care to recommend a video to start with?
If you're talking about the demoscene in general, here's demos sorted by popularity on one of the most important community sites: https://www.pouet.net/prodlist.php?order=views Most of them have links to yt videos.
Some of my favorite classic demos are "Sound Vision" by Reflect, "Desert Dream" by Kefrens and "Enigma" by Phenomena. All demos that were popular enough in the 1990s that they reached me and my brother's Amiga by way of modems and swapping. They're all very enjoyable without knowing much about the coding challenges.
I'd say my favorite modern Amiga demo is "Eon" by The Black Lotus. For C64 the good modern demos are too many to count (and by comparison, the 80s era demos aren't terribly interesting), but I think maybe "Lunatico" by LFT is my favorite. Again it's one that doesn't require coding knowledge to appreciate.