Text/HTML DataPart is a standalone DataPart that can be added to a DataPage to present a customized page with text, images, and links. Text/HTML DataPart supports custom HTML, CSS, and JavaScript code.  

Steps to create a Text/HTML DataPart 

1. In the upper panel, select the Add elements button.   
2. Select HTML > Text/HTML.  
3. Configure the page style and content. You can do it as plain text in an HTML editor or as custom code that supports syntax highlight. Text/HTML DataPart allows for adding app parameters with the parameter picker. Learn more about parameters.
4. Select Create. 

After creating a Text/HTML DataPart, you can edit its content and style by clicking the Edit Text/HTML button in the right panel.