Republic Day in India is the day when the country marks and celebrates the date on which the Constitution of India came into effect on 26 January 1950.

What are Fundamental Rights?
Constitution of India: List of All Articles
Constitution of India: List of All Articles
https://www.clearias.com/constitution-of-india/
The Preamble: What does it say, and what does it mean to India and its Constitution?
The Preamble: What does it say, and what does it mean to India and its Constitution?
https://www.legalserviceindia.com/legal/article-750-preamble-to-the-indian-constitution.html
Features of Indian Constitution