Microsoft has made its visitor behaviour analytics product, Clarity, generally available. If you’ve heard of this before, it’s because a beta version was announced nearly two years ago, but this seems to be the real thing, and it’s free. Clarity offers several useful capabilities including heatmaps and session-replay.
Clickmaps are a good place to start with Clarity. These tell you what page content users are interacting with the most. There are also scrollmaps, which show if your users are seeing the important stuff. And to get an idea of how individual users are interacting with your site, there are session recordings, which literally playback what visitors have done.