First of all you have to save your level in a new folder with file name “main.adofai” along with the song and decorations. Then zip the contents of the folder; that is your level file.
Then you have to use a file hosting website that can provide your file without user interaction. I use Google Drive with this tool to generate the link, but it doesn’t always work due to antivirus.
After you’ve done that you can share your link online and people can play by using the “open from url” option in the level editor.