Go to the Customizer.
Click the Featured Content section to expand it.
Enter a tag name in the Tag Name field. We used “featured” in the theme demo.
Click the Publish button.
Edit a post or page and assign it the Featured Content tag you set in step 3 to feature that post or page.
This does not work, you only appear to be able to add 1x featured content and then when you add a 2nd it overwrites the first. Therefore you cannot have 3 featured columns.
For example, I use a tag called Photos, it works fine and appears, on the left, I then try to do the same with Bio, it works but overwrites Photos on the left and now it’s Bio etc. It should become Photos on the left, Bio in the middle and lets say Videos on the right like the theme example.