This option allows you to enable or disable the preloader for the site. It is displayed while the content is being loaded. There are 3 preloader types: Animation, Image, and Font Awesome. Please go to Admin > Theme Options > Settings > General > Preloader.
When you choose animation type, just select a suitable animation available in the list. It also gives you options to adjust the color, background color, and size of the selected animation.
When you select the Image as the preloader type, you can display your logo or any other images, while the page is being loaded.
You will see a list of font-awesome icons to choose from in the FontAwesome library.