Change Text while scrolling

[Sophia2711]

I have different videos among each other and would like to show the caption at a certain scrollposition. Is that possible? How can I implent that?
I already have kind of a code snipet

const bodyTag = document.querySelector("body")
const sections = document.querySelectorAll("section")
const clientTag = document.querySelector("div.client")
const headerTag = document.querySelector("header")


document.addEventListener("scroll", function () {
  const pixels = window.pageYOffset
  
  sections.forEach(section => {
    if (section.offsetTop - 60 <= pixels) {
      const title = document.querySelector("div.title")
//       clientTag.innerHTML = section.getAttribute("data-client")
      clientTag.innerHTML = section.getAttribute("data-client")
    }
  })
})

[dani]

Waypoints does this...
http://imakewebthings.com/waypoints/

Ex in LAY, add/remove a CSS class on the 'index' : https://kiti.ca/kitty-care

Doesn't work as well on mobile... working on it.