If you wanna make this game using scratch, I recommend importing your sb3 file into Turbowarp and continuing to edit the game there. It's much more flexible and can easily make your project an HTML file, which is compatible with Itch io.  I am also planning to make this game with Turbowarp, and I have to warn you; it can be buggy at times. Hope this helps!

YOOO A SCRATCH USER, yes use turbo warp for the exporting on the game and since you can export it to every type of computer and html it is allowed for this jam