Is it obligatory to listen to the Imam's recitation in congregational prayer, or to the recitation of Imams from other neighboring mosques, and is it permissible to say "Ameen" with them?

The worshipper must listen attentively to the Imam's recitation in the loud prayer, according to the verse: "And when the Qur'an is recited, then listen to it and pay attention that you may receive mercy." As for the silent prayer, the worshipper focuses on their prayer and recitation and does not listen to anything outside the prayer, unless it is minor and does not invalidate the prayer.