Hey everyone! I hope I am able in my first posting to not sound too naive in my question

For my thesis, I would like to analyze the effect of a subsidy within a country, with the different regions being my units of observation.
This program lasted for 5 years, where the number of people being eligible for the subsidy differed per region and time.
I have collected the necessary data for: 5 years before the policy; 5 years where the policy was in effect; and 5 years thereafter.

Now I would like to measure the impact of the policy on another variable. Since so far I have done only simple DID analyses and not where the impact is heterogeneous over regions and time, I was unable to proceed.

Does anyone have any idea how to properly measure the effect of this policy in stata? Is there any command to just expand the DID to imply heterogeneity in time and regions or do I need to change my approach?

Thank you very much in advance, and I strongly anyone of you is so kind to help