1. Copy the embed code from the youtube video.
c. Copy the code shown.
2. From your Paper Settings Dashboard, click Web newspaper > Layout & appearance, then Ad units. Choose/click on which ad position to install your video.
Just to know....
A classic layout paper has five ad units:
A modern layout paper has four ad units:
3. Turn the toggle to ON, and click the Custom HTML option.
4. Paste the code from youtube into the Custom html code field.
5. Refresh the page to view the video.