Thank you for the repy, i followed your suggestion and find a way to divide "pck" files following this guide,
https://www.reddit.com/r/godot/comments/hf5yko/godot_workflow_for_multiple_pck_f...
after divide the "pck" files 4 different part, i got this error now.
"Failed loading file 'index.pck': Forbidden"
well, i know that what i must export as a "pck" file name is "index.pck" cause of games opening html file name is "index.html".
but my pck files are
1.pck, 2.pck, 3.pck, 4.pck
i don't know how itch.io read thi pck files, so how should i name them?
or is there diffrent solution to this problem?