Use the Asset Library
The images, audio files, and video files that you use in a project are collectively called "assets". The assets that you use in your projects are shown in the Asset Library. Assets get created when you drag or import an asset into the library or into your ad. DoubleClick Studio users can also access the images, videos, and other supported assets that they have in their Studio Asset Library.
You use the assets in the library by dragging them onto the workspace.