I've been thinking the issue last night (your trip to India as it seems to be the first time you go there).
Will it be a culture shock? 100%
Will it be a trip to remember? 100%
Is it worth going there? 100%
Staying is another question. I personally know it only as a tourist and I don't know how your friend has prepared you for it. I hope you will be picked up and not expected to travel on your own. If it's the latter, beware of the Rickshaw drivers. They like to drive you round after round and then charge you way more than fair. If you refuse, within 10 Minutes you're surrounded by a dozen of them (it happened to me). The taxis from the airport with traceable numbers are worth it! Incredible India is worth the title. Amazing. Impressive. Beautiful. Also with dark sides ofc.
What impressed me the most was how little some people need to live. They can take showers under a water tap not even one meter above the ground, sleep on cement floors without blanket, one set of clothing total. And at least the women still look pretty and wear golden earrings... A lesson in simplicity. And humbling.
If you happen to like it, the structures of society are much more different than you may grasp at first. If you marry there, it can bite you in the ass badly, though I suspect as a man it will be thousand times easier for you. Still then. Money counts. Much more than is ever spoken. Trust me. I'm married to one of those third world guys who claimed to not be into money at all. Now I'm under pressure to help out anyone in his family. It's not like he's gambling or anything. For him it's just being a good son. For me it means I have red numbers on my account rn at the beginning of the month and my purse for the kids and me till next payday. Don't become like me. And no, I never believed this could ever happen to me.

First it always comes differently, second than you think. The lesson of my life