I have a couple of questions I needed clarity on wrt to tax. Say an individual had bought crypto a long time back (2013-2015 period) and had barely sold any crypto for cash. This would obviously mean substantial sums in todays INR value if converted.

1) a) Is the person required to declare our crypto holdings in the Income Tax returns ?
    b) If answer to a is YES - What if a person has not declared any crypto holdings so far in any of the previous returns ?

2) How do people deal with exchanges doing down/missing records ?

3) Are crypto to crypto transactions taxable ? If so - how ?

Any other general advice that one needs to know for such individuals ? Trying to help a friend.