Creating section with multiple columns (old grid based appraoch)

You can add a new page section with multiple columns built in
Press the main + button on the page under all the current sections

Or, you can add multiple columns to an existing section
Add ‘Inner Section’ widget

Or you can set each widgets width to #% of the total width
Advanced > Positioning > Width. Setting each to 33.3% would give you 3 columns for instance

Add New Column

Right click its Edit Column icon to add a new column.