Always capitalize the following:
The first word in a sentence (किसी वाक्य का पहला शब्द)
E.g. I am Indian.
He is going to temple.
Hurrah! We won the match.
The pronoun I (सर्वनाम = I)
E.g. Do you think, I should go out?
I think I should go now.
I am not able to complete this work.
The first letter of a proper noun (specific name). (व्यक्तिवाचक संज्ञा का पहला अक्षर (विशिष्ट नाम))
E.g. This letter is from Chang.
Shreya is my friend.
Amit and Arun are friends.
The first letter of months, days, and holidays (but not seasons). (महीनों, दिनों और छुट्टियों का पहला अक्षर (लेकिन मौसम नहीं))
E.g. I am going to meet her on Saturday.
We will go there during Christmas break.
I like rainy season but this year there is no rain in July month.