Question - Rich Snippets

I host my website on Godaddy, and they have some SEO tools. Among them, there is one regarding something called "rich snippets". I am not an expert, so I just tried to follow the steps, and I received an html code, but the point is I don't know where to insert it, as I do not have on this theme a file called "index.html" as it was referred on Godaddy explanation.

Could you please help me? Thanks in advance.