This would be done within the Elementor editor.
Note: The elementor home page template would already need to be installed (under PremiumPress > Design Setup > PAGE BUILDER > Homepage Design).
Go to Elementor > Templates and select the homepage template to edit in Elementor. Once the editor opens you should see the carousel widget. Click on the widget then in the left menu you’ll see the available settings. Click on ADD IMAGES and add the images.