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.
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
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.