Is there a Sunnah of four Rak'ahs before and four after the 'Isha prayer, and is it permissible to combine them, and is it permissible to perform it after midnight? And are there six or eight Rak'ahs after the Maghrib prayer? And is its reward greater than reciting the Qur'an?

The regular Sunnah prayer for 'Isha consists of two rak'ahs after it. No specific number of supererogatory (nafl) prayers has been established before the 'Isha prayer, but it is permissible to pray four rak'ahs or more before it. It is also permissible to pray eight rak'ahs or more after 'Isha, as the matter is broad in this regard.

It is permissible to delay the Sunnah prayer of 'Isha until midnight.

The post-Maghrib Sunnah prayer is two rak'ahs. If you pray six or eight rak'ahs after it, there is no harm.

Engaging in supererogatory (nafl) prayers is considered better than reciting the Qur'an by some scholars, and the preference may vary depending on individuals.