You are right. It is on Youtube right here.If you are talking about the 1988 movie try youtube.
https://www.youtube.com/watch?v=BQ5Vh19WO1M
youtube is a lot cheaper than the DVD price Amazon wants to extort from someone.
The Invisible Boy 2014 is on Youtube to. I found The Invisible Boy 1957 to, but not on Youtube.youtube is a lot cheaper than the DVD price Amazon wants to extort from someone. US$51.
If the movie is the 1988 version. There are two different versions of "The Invisible Boy." 1957 and 2014.
The 1957 movie is available as an extra on the DVD or BD of "Forbidden Planet."
https://www.youtube.com/watch?app=desktop&v=5CJWLPoDRrI
Shortened link:The Invisible Boy 2014 is on Youtube too.
https://www.youtube.com/watch?v=5CJWLPoDRrI
Tubi has that movie Forbidden Planet. You can get that with yt-dlp or any Youtube downloader.The 1957 movie is available as an extra on the DVD or BD of "Forbidden Planet
https://tubitv.com/movies/100012215/forbidden-planet