Scroll function from DevEd tutorial is not working

I've watched this tutorial https://www.youtube.com/watch?v=oUSvlrDTLi4 and I was doing the same thing as here, I only replaced var to let with ES6 standard.

function scroll(target, duration = 1000) {
  target = document.querySelector(target) + window.scrollY;
  let targetPos = terget.getBoundingClientRect().top;
  let startPos = window.pageYOffset;
  let distance = targetPos - startPos;
  let startTime = null;

  function animation(currentTime) {
    if (startTime === null) startTime = currentTime;
    let timeElapsed = currentTime - startTime;
    let run = ease(timeElapsed, startPos, distance, duration);
    window.scrollTo(0, run);
    if (timeElapsed < duration) requestAnimationFrame(animation);
  }

  function ease(t, b, c, d) {
    t /= d / 2;
    if (t < 1) return c / 2 * t * t + b;
    t--;
    return -c / 2 * (t * (t - 2) - 1) + b;
  }

  requestAnimationFrame(animation);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.a {
  width: 100%;
  height: 100vh;
  background: green;
}

.b {
  width: 100%;
  height: 100vh;
  background: yellow;
}

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <div class="a">
    <h1 onclick="scroll('.b', 1000)">Scroll</h1>
  </div>
  <div class="b">
    <h1 onclick="scroll('.a', 1000)">Scroll</h1>
  </div>
</body>

</html>

However, it doesn't seem to work.

Solution

Change the function name to not conflict with window.scroll.
target should be the element itself or document.querySelector(target).
target was spelled wrong on the second line of the function.

function myScroll(target, duration = 1000) {
  target = document.querySelector(target);
  let targetPos = target.getBoundingClientRect().top;
  let startPos = window.pageYOffset;
  let distance = targetPos - startPos;
  let startTime = null;

  function animation(currentTime) {
    if (startTime === null) startTime = currentTime;
    let timeElapsed = currentTime - startTime;
    let run = ease(timeElapsed, startPos, distance, duration);
    window.scrollTo(0, run);
    if (timeElapsed < duration) requestAnimationFrame(animation);
  }

  function ease(t, b, c, d) {
    t /= d / 2;
    if (t < 1) return c / 2 * t * t + b;
    t--;
    return -c / 2 * (t * (t - 2) - 1) + b;
  }

  requestAnimationFrame(animation);
}

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    .a {
      width: 100%;
      height: 100vh;
      background: green;
    }
    
    .b {
      width: 100%;
      height: 100vh;
      background: yellow;
    }
  </style>
</head>

<body>
  <div class="a">
    <h1 onclick="myScroll('.b', 1000)">Scroll</h1>
  </div>
  <div class="b">
    <h1 onclick="myScroll('.a', 1000)">Scroll</h1>
  </div>
</body>

</html>