I found the comments and conversation here: https://animationpaper.com/forums/topic/suggestions-and-impressions/
But the thing you are interested in doesn’t seem to be covered. So I’ll answer you here:
You need to export your animation and make it into a mp4 file. In Alpha 3 you will have to export as a stack of png images and use other software to convert them to mp4. An efficient and free way of doing that is by using FFMPEG. But it is a bit technical.
Another way is to wait just a few days/weeks for our next release (Alpha 4) – which has build in export of mp4 (and mov/prores).
mp4 is compatible with browsers, so you can show it directly on a website – but of course it also depends on how the website is setup and if you as a user have the necessary access. But that is beyond me 😉 If you want to upload to youtube or elsewhere, mp4 is very well suited for that too.
I hope this is helpful to you.