In your Builder pages you can take an existing layout and reap the advantages of Columns without having to redo your layout.
In case you missed the advantages of Builder's Columns feature, like instant repsonsiveness with no media queries or sizing attributes required on your side, check out Using Columns to Build Responsively.
While you can build your page with Columns from scratch, if you don't, you can convert it later.
You can convert parts of your page to Columns if the elements you want to convert to a columns layout are already contained inside another element or Builder Block.
In this video, the existing layout had three Text blocks inside a Box. To convert to columns, select the Box block—you can check that it's selected by viewing the Layers tab. Then, in the Layout section of the Style tab, click the Columns icon under Child Layout.
In the last video, the Text blocks were already inside a Box block. If you don't have a container around the elements, you can still convert to columns.
In this video, the existing layout had three Text blocks with nothing around them. To fix that issue, select one of the text blocks, then Shift+click each of the others so that they are all selected. Then, right-click on one of the selected Text blocks and choose Group selection from the context menu.
If you check over in the Layers tab you'll notice there is now a Box block around your Text blocks.
Check the Style tab in the Layout section and you'll see the Columns option is now enabled. Click it and, magically, you have columns.
Note that your layout can have any number of columns you like; the only limiting factor is how well your content lends itself to narrow columns if you have many.
Now that you're an expert with Columns, you'll probably want to delve deeper into responsive design. Intro to Responsive Design is a great place to start.
