Question

Why doesn’t India have a state religion ? Can a citizen be discriminated on the grounds of their religion in India ?

Answer 1

if India had state religion then it could be a civil war among the states of India
India is NOT discriminated on grounds of our religions as all type of people live here....

Answer 2

Hey dear!
_________

Your question has two parts-
i. Why does not India have a state religion?
ii. Can a citizen be discriminated on the grounds of their religion in India?

I am giving here answers to both the questions separately.

i. Why doesn't India have a state religion?

India is a multicultural country where diverse religious communities live like- Hinduism, Christianity, Islamism, Buddhism, Jainism, Sikhism, Judaism, Zoroastrianism etc. 
Moreover, Many states in India like Andhra Pradesh, Maharashtra. Tamil Nadu etc were formed on the linguistic basis.
Instead of sticking to a state religion India preferred to be secular to respect all religions and keep the country free of any tormoil or conflict on the isuue of religion.

legal provisions: 
Right to Freedom of Religion is a fundamental right discussed under Articles 25 to 28

ii. Can a citizen be discriminated on the grounds of their religion in India?

Right to Equality-Article 15 Prohibits discrimination on grounds of religion, race, caste, sex or place of birth and therefore no institution run or aided or funded by govt can deny admission only on the grounds of religion.

_______________________________________________________
Problem in understanding any answer or part there of , feel free to ask.