You can add a person a Cloze List in two ways.
OPTION 1: ADD A CONTACT TO A LIST IN THEIR PROFILE
OPTION 2: ADD A CONTACT TO A CLOZE LIST ON THE PEOPLE SECTION
1.) In the People section search for the person or group of people you would like to add to a List. Scroll down and tap on the checkmark next to the people you would like to add to your List.