Thanks for playing! Glad you had fun with it :)
Uploading this game was fairly straightforwards for me - I bundled the game using esbuild, then put the .js file that esbuild generated as a script inside of index.html. When you upload an in-browser game to itch, it’ll automatically find the index.html page and display that.
It’s hard to help your specific issue without more details. Are your assets loading locally, and only not working when you try to upload to itch? Where are your assets located? This game is open source, you can see the source code here if that helps - you can see my assets in the ‘public’ folder, which also contains the index.html