Theme doesn't look like preview and doesn't work

Hello,

I installed the theme i-transform. The preview shows an image in and text in the blue bar above the section where the posts are displayed.
This blue bar is empty and I can not figure out how to add content or get posts displayed in there (I assume specivic posts will be displayed there)

I’m completely new to wordpress because I struggled every time I tried to get into it. Exactly as now. I wasted now 3 hours of search and sleep time.

Can somebody help me or give me a hint where to search in such a situation. I read 5 pages with listet results on this site here. But no chance.