Travelling to India soon, what SIM to take?

Hi all! I'm travelling to India in a month or so, and as someone who likes to stay online and stay connected (don't we all?) I'd like to invest in a SIM card when I visit. I'll be staying in Kolkata, with a short 3-hour layover in Delhi, where I thought I'd purchase a SIM. I've heard Jio is the best, but I really don't mind.

Prices seem cheap for Indian SIMs, and pre-purchased travel eSIMs where I live (Australia), seem very, very expensive in comparison.

I've also heard that getting the SIM once you visit is an ordeal of its own. There are no SIM shops at the Airport in Kolkata, and you need ID and an Indian's verification (which I can do, just not preferred haha) to get one in Delhi. I'm also 17, I'm not sure if that would make a difference.

Would it be easier to purchase an eSIM before travelling? Or should I get the better deal and take my chances at the Airport? What should I prepare if I do that?

Thanks all!