based on what i'm seeing, you don't have an index.html file (duh)

this is like the Project.xml file in any fnf mod. Get rid of it, and everything is gone. reduced to atoms.

you probably zipped the wrong thing.

here's where the folder is

<project folder>/export/release/html5

in this folder should be 3 more folders: bin, haxe, and obj.

you want to zip the bin folder.

that's all you should have to do to fix it. if it doesn't work after it uploads, it probably has to do with discord code, but i digress.