To add custom text to your product list widget you'll need to log into your website builder and find the relevant widget you'd like to edit.
1) Right-click on your product list widget
2) Click Connect to data. In the list you can choose which text you'd like to appear as the bottom left text and the bottom right text. For example, in the picture below, bottom left text is duration and bottom right text is meeting type.
3) To add a custom text in addition to the bottom left text and the bottom right text, click you widget and click Advanced in the bottom of the menu. Under bottom left prefix and bottom right prefix you can add custom text. For example, in the picture below, bottom left prefix is "Duration:" and bottom right text is "Where to meet?".