This displays the testimonial added to the site. It again has the General and the Custom CSS section. First, the General section provides different options for the way in which the testimonial can be displayed. You can add the number of posts by selecting post per page. Post-offset is excluding the latest posts from the total number of posts you want to display. You can select the date order of the post and enable excerpt option and set excerpt length as you need.
You can select the style between the chat view and the normal slider. You can also add columns, elements, ID and class/classes as shown in the images below:
Then, after the General section comes to the Custom CSS section