TOC on left, On this Page on right

I really like the TOC on the left. I think it would be nice to have the On-this-page on the right if the screen is big enough. Check out this page from MS:

https://docs.microsoft.com/en-us/windows/wsl/wsl2-mount-disk

See on the right it says "In this article". That's like our "On this Page"

I tried to do this, but I'm bad at CSS.

I just experimented live inserting CSS and got this:

.tocset .tocview {
    position: fixed;
    overflow-y: scroll;
    float: none;
    left: 0;
    top: 0rem;
    bottom: 0;
    width: 14rem;
    padding: 0rem 0.5rem 0.5rem 0.5rem;
    background-color: hsl(216, 15%, 70%);
    margin: 6rem 0 0 0;
    }
    
.navsettop {
    position: fixed;
    z-index: 1;
    background: #a7b0be;
    top: 0;
    left: 0;
    margin-bottom: 0;
    border-bottom: 0;
}

  .tocset .tocsub {
    position: fixed;
    overflow-y: scroll;
    float: none;
    right: 0;
    top: 0rem;
    bottom: 0;
    width: 14rem;
    padding: 0rem 0.5rem 0.5rem 0.5rem;
    background-color: hsl(216, 15%, 70%);
    margin: 0;
    }

It's okay but it is not flexible to the size of the screen, nor does it really work, because it overlaps maincolumn.

Please O CSS Ones, help me!

Start by locating the CSS that renders .tocset, .tocview, and .tocsub, then compare the current layout with the linked Microsoft example. Done means the On-this-page navigation appears on the right at sufficiently wide screen sizes without overlapping the main column and remains usable at smaller sizes.