1. From your dashboard, go to the Appearance > Customize >Homepage sections > Testimonial Section  

2. Show/Hide this section

3. Now add the Title, Subtitle, Text in fields

4. Now select the Testimonial Column

5. Now click on the Add New Item

6. Add Image, Title, Subtitle, Text, Link, and Shortcode in the Testimonial Item

7. Now click the delete field to delete the Item

8. Hit on the Publish

See Live Preview:-