Question

what were the difficulties faced by the constitution

Answer 1

Indians was emerging from the status of subjects to citizens.
Independence of India was followed by partition over religious differences and large scale violence on both sides of the border.
The British had left the decision of accession to either India or Pakistan or remain as independent entities to the princely states and their joining the country was a difficult task.
India was a vast country with multiple regions, language, culture, customs and beliefs. This diversity was a hindrance in framing the constitution.