Currently, It is not possible to delete the cover slide, but we do have designs which allow you to add photo on the cover page with text or you can delete the text and have a blank cover slide:
Please search the design with the following keywords:
We Love You
You can delete all the context from the first page so you have a first blank page.
The below designs allow you to add photo on cover slide and change the text and title for most of the designs.
A Beautiful Tribute