If you would like to insert your Google Drawings into a Google Slides presentation here is how to do it.
Go to Google Drive and click on the “New” button to create a Google Drawing. You can do this for a variety of reasons. One reason is to create a graphic organizer for a background. See @MsDrasby’s guest blog post on creating math manipulatives with Google Drawing.
Publish to the Web
Use the File menu and choose “Publish to the web.”
By inserting via URL, the image will update if you update the Google Drawing image.