In step 3 Customize, look to at the bottom right of your screen to see Layers
As you add your text boxes or image(s) to your project, you will see the list of the details titled as Text 1, Image 1 (See Below)
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Select the object, and click on the Trash Bin icon to delete and remove the object from your current project.
To Unlock the listed Text: (Editing the Text or Image Boxes)
When editing the text or images through Layers, please make sure the objects are Un-locked
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