Is it recommended to make qunut in prayers for our brethren in Gaza so that Allah may lift the aggression of the Jews from them, and in which prayer should it be?

Yes, it is sunnah for Muslims to supplicate for their brethren in Gaza for victory and protection against their enemy, and for the destruction of the Jews and those who assist them. The supplication should be recited aloud by the Imam, with the congregants saying 'ameen' behind him, and an individual should perform qunut in their prayer.

Indeed, qunut in times of calamity has been authentically reported from the Prophet, peace and blessings be upon him, on several occasions. As in the hadith narrated by Anas ibn Malik, may Allah be pleased with him, that the Prophet, peace and blessings be upon him, performed qunut for a month during the Fajr prayer, supplicating against tribes that had betrayed seventy Companions. He also performed qunut during the Maghrib and Fajr prayers, and he performed qunut in all five prayers.

Among what can be inferred from the hadiths is the permissibility of qunut in times of calamity, and that the Prophet, peace and blessings be upon him, performed qunut in Fajr and Maghrib, and in all prayers, though most of his qunut was in Fajr. Qunut in obligatory prayers is not prescribed unless a calamity befalls the Muslims that necessitates qunut. In such a case, it becomes permissible for every worshipper to perform it in Maghrib and Fajr, or in all prayers, and the qunut ceases once the calamity is averted.