How can i make a particular function work on page A after pressing a button in page B?

Question

Building an interaction between web pages. Like making function work on the current web page after moving out of the previous page

Answer 1

single page

toggle display of different section elements to appear as if they are different "page"

like this one:
https://code.sololearn.com/WD8Q8oa4BDl0/?ref=app

Answer 2

@Ipang yeah

Answer 3

Just to be clear, so you have written a JS function in A.html and you want to execute that function from B.html. Is this what you mean? or is it the other ways around? or it's a whole different idea?