While Article 5 provided for the initial citizenship, Article 11 empowered Parliament to regulate further citizenship laws, leading to the Indian Citizenship Act, 1955. Article 5 in Constitution of India - Indian Kanoon
The person has been ordinarily resident in the territory of India for at least five years immediately preceding the commencement of the Constitution (Jan 26, 1950). Context and Significance 5_6321088607167709645
Articles 5 to 11 comprise Part II of the Constitution, dealing specifically with citizenship. While Article 5 provided for the initial citizenship,
Either of the person's parents was born in the territory of India. leading to the Indian Citizenship Act