Are you on the pro version of the theme? Do you have the latest package downloaded? Have you followed these instructions?:
https://startupwp.com/topic/setting-up-the-slider/
In either the free version or pro, from your main admin menu, simply navigate to:
Appearance > Startup Options
Then among the checkbox options you’ll find the option to disable the slider. Additionally you may want to check under Plugins and make sure that any plugins you aren’t using are deactivating and then deleted.