What should he do?

The one who is in a country where the punishment for zina is not implemented.

He should strive by advising and reminding them to implement this punishment.

And establish the law of Allah, the Blessed and Exalted, and advise people not to fall into zina and other such things. The important thing is that this is a great shortcoming.

Not implementing the punishments is a great shortcoming, and Allah, the Exalted, will hold them accountable for that, those who are the rulers and do not implement these punishments. But you, as an individual,

they are accountable, and your duty is to call to Allah, the Blessed and Exalted, and to call them to implement it.

The limits set by Allah, the Blessed and Exalted.