In Tempera Settings> Presentation Page Columns, select the source of the content and how many columns you want in the row.
If you choose Widget Columns as your source:
Go to Appearance > Widget > Presentation Page Columns > Cryout Columns (drag the widget into the Presentation Page Columns box from the widget list on the left – you can have as many as you like) and then add your content within the Cryout Columns settings.
~ Wayfarer