Inside the file you downloaded from CodeCanyon you'll see a folder named "examples" inside that folder you'll find several .json files containing some of the buttons of the live preview.
Import Buttons:
You can import the
all buttons.json file in order to get the examples into your Wordpress installation, or choose to import only some of them.
You can import examples by going to the
Import/Export option in the Whatsapp Chat admin panel. Then scroll down to the
IMPORTER section and select a .json file, then just click
Import.
Export Buttons:
You can also export your buttons (in case you wish to import them in another Wordpress installation). In order to do so go to the
Import/Export option, choose the buttons you wish to export and click the
Export button. A .json file will be downloaded to your computer.