I'm considering travelling to India, I've been to countries like The Philippines before, but what makes India different in terms of positive or negative experiences?

I'm trying to plan out an itinerary of India travel starting from Mumbai then heading to Kerala & Tamil Nadu alongside possible plans for a Northward flight(though that's a bit more complicated as we don't know if we're doing Kaziranga or Delhi in tandem with the Himalayas)

A lot of people online have warned me about certain sanitary cautions and lamented to me about how dirty major areas of the country are or that you have to be careful about the people, but as an Asian American, I don't really understand if it's on a different level when compared to The Philippines.

Having been inside Manila & Cebu, there's a massive amount of poverty and trash, alongside a huge amount of beggars and slums, so I assume that many of India's places are the same, but I'd love to hear from others about this?