Your site has some commonly used modules already preconfigured. These include:

• Image (type: Custom), which holds the image beneath the menu. This is a Custom module that you can edit to change the image.
• Popular Tags (type: Tags - Popular), which will appear if you use tagging on your articles. Enter a tag in the Tags field when editing.
• Older Posts (type: Articles - Category), which lists out articles by categories.
• Syndication (type: Syndication Feeds), which allows your readers to read your posts in a news reader.
• Login Form (type: Login), which allows your users to access restricted areas of the website.

Each of these modules has many options which you can experiment with in the Module Manager in your site Administrator. When you are logged in you can also select the edit icon in the top right corner which will take you to an edit screen for that module. Always be sure to save and close any module you edit.

Joomla! also includes many other modules you can incorporate in your site. As you develop your site you may want to add more modules that you can find at the Joomla Extensions Directory.

Your home page is set to display the content like slideshow, image, text, blog content and so on using Gantry layout manager. The Layout Manager in the Gantry-based theme administration interface provides several options for setting up the layout of the theme's Outlines.

You can change the content by editing the Home Layout settings in the Layout manager in your site template administrator. Go to System -> Site Template Styles -> here you can see the Home layout style, i.e Veno Pro - Home (Template Name - Layout Name).

The layout(Home in this case) consists of several different sections, particles, each with its own set of settings that enable you to customize the behavior and look of your site on the front end.

You can find out all about Layout documentation in Gantry5 Layout Manager Guide.