First, to add the image in question:
Go to your WordPress Dashboard.
Click on Media > Add New
Drop files to upload or select the files
Click on Save.
Then, edit the Home Page slider
Go to the Home Page
Click on Enable Visual Builder on top of the page.
Edit the slider Module
Click on the gear in the gray box
Click on the gear at the left of New Slide
The content box will open, you’ll be able to edit the title and the background photo
Click on Check. Always save!
5. Click on the “…” in the purple circle, then Save
6. Exit visual builder.