On the Captions tab, you can add non-roll footage at the start of a specific caption to make your video dynamic and not boring.
Click the B-roll icon in the caption,
or click the Search B-roll button by clicking on a specific word
You can then search for B-roll footage directly with those words.
And all you need to do is add a duration for the non-roll footage.
You can also search by movie title, actor, or scene to use movie footage as a video roll,
You can also upload your own video files to use as non-roll footage.