The fonts menu displays a list of available fonts which you can apply to your text.  

The computer of the person visiting your website will apply a different font to your text if it does not have the font you have applied installed.

In order to minimize the chances of this occurring, we recommend you only apply fonts from the subset of fonts listed below the section Web safe fonts to the text in your web pages.  A warning will be displayed when saving a website with non web safe fonts applied. 

Any font can be applied to text which is converted to a graphic on export such as the text used in the headings of the web templates. Simply group your text to cause it to be exported as a graphic.