Hi rope,
We would like to answer your questions in detail as follows:
<blockquote>Knowing What’s Happening is Good. Making it Happen is Better</blockquote>
This is a page title which you can find at Page Heading box of Page Display Options inside Home menu item backend.
<blockquote> where I can configure the header, where I can set data-category for it</blockquote>
The header section of JA Beranis template contains the logo, navigation and search module. You can use our template demo builder to install a JA Beranis demo and refer the menu item settings to know how we configure the category/blog.