My colleagues and I have used inline CSS on <div> tags to structure content in a table style. Accessibility ought to be a key factor to consider when you do this as screen readers will attempt to read the content linearly, so my recommendation is to keep the 2 column format. It boils down to a basic starter template as shown below: Try this code in the html view of any RCE editor enabled area of Canvas:
<div>
<div style="width:100px;float:left;display:inline-block;">
</div>
<div style="margin-left:100px;">
</div>
</div>
It might help to put some filler text in each div so you can switch back to the visual view of the RCE and add your content using the Canvas RCE toolbar and keyboard. You should be able to switch back to HTML view as needed.
When you are ready to make a new section repeat the pattern.
Hope that helps.