The HTML Feed Generator works in conjunction with the RSS Feed Generator.  To configure, go to the Configure Site > RSS Feed Settings tab. 

As noted in the user manual article, How To Easily & Automatically Create An RSS Feed For Your Website , on the top of this page you can configure your RSS Feed settings.  Your HTML Feed will take the configuration settings for which apps to include posts from in this section.

Then scroll down for the HTML Feed and HTML Feed - Email settings:

Choose your HTML Feed file name and customize how far back to include posts from here.  To embed your HTML Feed into your website, copy/paste the Placeholder Text provided here into your page (Admin Panel > Add/Edit Page) Content Editor Box, where you want your HTML Feed to display.  You also need to make sure that you either manually run the HTML Feed Generator by clicking on the link provided on this configurations page to do it, or set up a "cron job" to run it automatically from your web hosting control panel, (refer to setup instructions here).

In the "HTML Feed - Email" section, you can configure how often you plan to run the HTML Feed Generator Email, choose to send the emails to all of your mailing list or to select mailing group(s), and also customize your email and email subject.  You can also click on the link provided here to manually run the HTML Feed Generator Email, and/or you can set up a "cron job" to run it automatically from your web hosting control panel, (refer to setup instructions here).