1) Select a prop by clicking on it.
2) Right-click to open a menu and select Copy or use the keyboard shortcut CTR C (⌘ C).
Alternatively, select the Copy icon on the top bar.
3) Right-click on the scene and select Paste or use CTRL V (⌘ V) to duplicate the prop on the scene.
Alternatively, select the Paste icon in the video maker.
Learn more about keyboard shortcuts in this article.