css elment top down page code example

Example 1: postion on window top css

#sideBar {
    position: fixed;
    display: block;
    top: 50%;
    left: 10px;
    margin: -100px 0 0 0;
    height: 200px;
    width: 50px;
}

Example 2: html css bring to page top

window.scroll({
  top: 0, 
  left: 0, 
  behavior: 'smooth'
});