Screencastify videos can be inserted into Google Slides. We can only insert videos shared onto a YouTube Channel. Create a video, add it to your YouTube channel, and get the link to the video.
Click the copy link button to the right of the link.
Go over to Google Drive and create or open an existing Google Slide document. Select a slide where the video will be inserted.
Click on Insert in the menu, and select Video.
Click on the URL option and paste the URL copied from Screencastify. A preview of the video should appear below the link.
Click the “Select” button to insert the video onto the slide.
Position the video on the slide and resize the video using the corner handles.
Preview the video by double clicking the video thumbnail on the slide.