"I was in India."

Translation: मैं भारत में था।

[Soumya603644]

It could be both था or थी

[JANHAVISAN1]

Yes

[Brian766884]

Why isnt it meine?

[deactivated user]

"Meine" Or "मैंने" means "I" but is used when it is followed by a verb done by the speaker like in,
"Meine khaana kha liya hai" Or "मैंने खाना खा लिया है।"
which translate to "I have eaten the food". Here "Mai" Or "मै" is used because the "I" in the sentence is not like the one mentioned above.

Hope this helps