I received an HDFC IOCL credit card with a 25,000 limit when I turned 18, i applied in March 2022.
I have a 3k FD and a 1k RD at the time, used debit for online purchases, and made at least one NEFT transaction from my other accounts each month to my HDFC account while maintaining a balance of roughly 20k. I was a member of Preferred Banking at the time, too. While the offer was not visible on the offers page of NetBanking at the time, I simply checked by using the apply option. I believe this helped me receive a preapproved offer.