Updating data at related collections

hi folks,
how can i update other collections after update current one.
i’m using VUE.js as client frontend and dont want to send many request to server update all other collections.
I found web hooks section but there is no any example to follow.
how can i do those actions like before_insert or before_update.is there any sample or guide to follow ?
i was using directus before and using hook functions for it.check here
also what is at “cockpit\storage\collections\rules” folder and read,update etc files in it?
can we use them to manipulate form data or they are just for view ?