Hello,
The Slides In the WoodMart Hardware demo depend on which page builder is being used on your website.
If you are using WPBakery, navigate to Slides > Edit the slide with WPBakery and you will be able to manage the slides, images, and other slider settings from there.
Here is the guide: https://xtemos.com/docs-topic/how-to-create-a-slider/
If you are using Gutenberg, open the page in the WordPress editor, locate the slider block, and edit the slider settings directly inside Gutenberg.
See Screenshot for better understanding: https://postimg.cc/WDsr7MJm
You do not need to disable Gutenberg. Please first check which builder you are using from Theme Settings > Other or check how the homepage is built by editing the page and see whether it is WPBakery, or Gutenberg. Then you can manage the slider from the corresponding editor.
Best Regards