Two approaches are available to display WordPress posts contents in multi-column, something like this.
The first approach is to use a WordPress plugin called Column Shortcodes. It is very good plugin with high flexibilty and ease of use particularly for those who do not have much context about web designing and willing to do things fast. However, the plugin is not compatible with all themes. For instance, texts in Freak theme do not align properly using Column Shortcodes as intended.
The second approach is more time consuming because it requires to apply some CSS styles to HTML codes. The easiest way is to switch to HTML editing of the post in WordPress that you would like to make it multi columns, then add
float style. As an example output of following code is a two column page with a small gap in between.
The output of the code is this picture.