10% of companies in the index can be shuffled/changed in a year, based on exchange’s decision.
In a given year 50(10% of 500) New will come , 50 will exit or weightage will be changed.
Per my knowledge list of current companies can be found here
https://www1.nseindia.com/products/content/equities/indices/nifty_500.htm
List of the companies entered / existed yearly basis can be found here,
https://www1.nseindia.com/products/content/equities/indices/archieve_indices.htm
Not aware of any straight forward way to check that.
May be Seniors in this forum could share if any easy way.