WP theme comes bundled with Slider Revolution.
Bundled plugins do not require activation license! Please see Plugins License page.
To add slider without WPbakery Page Builder, use Shortcode Method To add slider using WPbakery Page Builder, simply add Slider Revolution element to the page. Importing Slider
You can import demo sliders by going to Slider Revolution/Import Slider and browsing file in main files download package inside the demo-import folder. By default sliders importing automatically.
Seeing a red warning where a revolution slider should be? You just need to import the demo slider included in your themes demo-import folder provided in your package