Is it permissible for the Imam to recite specific surahs a certain number of times before the Friday prayer upon hearing news of a death? And is it legislated for the worshippers to participate with him? And is it obligatory to listen attentively to the Imam's loud recitation of Ayat al-Kursi after the prayer?

Reciting the Quran and dedicating its reward to the deceased is permissible. However, allocating the recitation of specific surahs at a particular time is not permissible, and you should not participate with those who do so. Rather, you should occupy yourself with other remembrances and advise them. As for their loud recitation of Ayat al-Kursi and other post-prayer remembrances after the prayer, there is detail concerning this, and it is better for you to listen to the Quran and then perform the remembrances.