How is zakat calculated on inheritance funds preserved in the Guardianship Council for Minors' Funds for the period between the father's death and the son's receipt of these funds, taking into account price inflation and currency devaluation?

May Allah reward you for your diligence in paying zakat (definition). There is no sin upon you for delaying its payment for that period due to your inability. What is obligatory upon you now is to pay zakat for that period. The general rule is that you should pay the same amount that was due, even if the purchasing power has changed. However, if the depreciation of the currency is excessive, then you should pay the value, because zakat is a debt upon you, and a debt is paid in the same currency unless it has collapsed or depreciated excessively.