itch.io

webgl is so you can run it on the webpage in itch, like if you see for example on my game.
on unity at least it's simple as installing the webgl addons and changing build mode to web, then building the game, often you don't have to change any code besides maybe some QoL changes. once you built it you just upload it to itch as usual and you select "this game will be played in browser"

on other engine the process will be mostly similiar, hope this helps :)