How is the Sunnah of "Bilal's Footsteps in Paradise" prayed? And does it suffice for the Sunnah of the mosque if performed therein? And should it be performed during times of prohibition, or should it be delayed?

This prayer is called the Sunnah of Wudu, and it is not limited to a specific number of units or a particular recitation. Rather, a Muslim may pray as much of it as they wish. The proof for it is the Hadith of Abu Hurayrah, may Allah be pleased with him, that the Prophet, peace and blessings be upon him, said to Bilal: "Tell me about the most hopeful deed you did in Islam, for I heard the sound of your sandals in front of me in Paradise." He said: "I did not do any deed more hopeful to me than that I never purified myself with ablution at any time of night or day, except that I prayed with that purification what was decreed for me to pray." This prayer suffices for Tahiyyat al-Masjid (greeting the mosque), and it is permissible to perform it during times when prayer is ordinarily prohibited.