This is a Choice Benefit available to Diamond Medallion members. Here is the exact wording from the Delta app:

Gift Gold Medallion Status to 4 Skymiles Members of your choice. Their Status will be valid through January 31, 2028. Selecting 4 recipients at the same time will use 1 Choice Benefit. Please note: You must choose all recipients in a single selection. Once submitted, you cannot add, remove, or swap recipients.

Buyer will need to provide First Name, Last Name, and Skymiles number for each recipient. Gold Status will be active within 48 hours of submission.