Pricing widgets are a list of items/groups that can be organised into sections with prices next to each one.  Each line can be set as a one-off (for example, an installation cost) or set to repeat on a schedule (such as a monthly cost for website hosting).

The items/groups inside a pricing widget can be specified in the menu by going to Admin > Settings > Selling Items > Services.

To specify where a pricing widget, when editing a page, click Insert then under Insert System Prompt, search for Pricing Widget.  To see what it will look like, click PDF Preview - you will see some sample data filled in.