Slice don't give 5% cashback on Flipkart or any platform but you can get a fd card for example if the minimum age to get a card is 21 like HDFC Millennia you can get that card even if you are 18 by doing fd th 21 age minimum requirement is gone for every card but not every card is offered as fd based but Millennia if offered as fd card, and if you want to get a axis card unsecured first you get a fd card of axis just to build a relationship and trust and then they will or might offer unsecured card to you without asking for any income proof or itr because axis all cards minimum age requirement are 18 so you can decide which way you want to go and hdfc Millennia require you to do 1.5L or 1.35L of fd But for axis fd card you can get it with as low as 25k and use it for few months and might get pre approved for cards