Three-column layout

https://www.benopp.eu/positionierung.html
On this page, I’m trying to achieve a standard layout similar to this:
However, the course I’m doing this for had different instructions from the ones found under that link so I followed those first. The problems that I can meaningfully identify for now are:

  1. the tumbeasts in the right column are overlapping each other, even though I tried to separate them with a
    hr { height:0px; clear:both;}
    Before I inserted that, they were next to each other - I want one below the other.
  2. the middle column starts below the two outer ones - I would like them to align at the top, all starting in the same row of pixels.