You can import a web build preset (aka download something config it and it will spit out your web files) for Godot's export window; https://foosel.net/til/how-to-export-a-godot-4-game-to-run-on-the-web-on-itchio/ looks like a good guide for this. You need to hit the add button to find a preset. NOTE itch expects the game files to be zipped up and that they are called index (name in the export configs).
Shameless plug of my game, also hope this post helps you!
https://itch.io/jam/brackeys-14/rate/3836553 <- Baking Hazard!