Using the camera on your Chromebook you can easily insert a snapshot in a document (Docs, Slides or Sheets document).
1. In order to do that you have to have your document open and select Insert > Image...
2. You will presented with different sources where you can get your image from, in this case we want to select Take a snapshot
3. If you are presented with a request to allow or deny Flash Player access to your camera and microphone, select both Allow and Remember
4. If the Application you're using asks for permission you can click on Allow once more
5. You should now be able to see yourself in the screen and take a Snapshot by clicking on Take Snapshop
You can take several and then select the one you like the most to be inserted in your document by clicking Select so you can resize and position it where you want.