How to activate lightbox?

Hi there! I got the Bold Photography Pro theme for my website http://willigphotography.com and are slowly learning how to rebuild a website on my own. Also, I did install and activate all recommended plugins. My goal is to have the option to click on a picture from my gallery i.e. http://willigphotography.com/portfolio/mother-nature/ and to get the lightbox option that I am seeing at the demo of the Pro version (https://catchthemes.com/demo/bold-photography-pro/style-guide/gallery/#jp-carousel-5638). The carousel option of the Catch Gallery plugin is enabled. How can I get the same feature after clicking on the picture as displayed with the demo? Thank you in advance - and a happy new year! Best Regards from Bavaria, Germany, Thomas