Creating a Testimonial Page

Hello – please can you give me some assistance

I really like the Testimonial format on this demo page but cannot see how to build this.

https://hb-themes.com/themes/highend_wp/testimonials/

I cant see options in Testimonial Box or Testimonial slider that exposes the Author image or puts in the ‘speech bubble frame’ around the words. I cant see testimonial as a page template either.

How can I get a testimonial page that looks like your Demo?

Many thanks!

/James