Is entering the day after 12:00 AM considered night for the purpose of supplications specified for the night, and can the virtues of these supplications be known in detail, along with a request for more easily memorized supplications?

It is best to adhere to the supplications (adhkar) authentically reported from the Prophet, peace and blessings be upon him, in terms of their number, description, and time. Examples include reciting "La ilaha illallah wahdahu la sharika lah, lahul mulku wa lahul hamdu wa huwa 'ala kulli shayin qadir" (There is no god but Allah, alone, without partner. To Him belongs all sovereignty and all praise, and He is over all things competent) one hundred times, and "Subhanallah wa bihamdihi" (Glory be to Allah and praise be to Him) one hundred times, and seeking forgiveness one hundred times, as well as the morning and evening remembrances. It is recommended to acquire the book "Hisn al-Muslim" (Fortress of the Muslim) or Imam Al-Nawawi's "Al-Adhkar." The day begins at dawn, and the night begins at sunset. And you must adhere to the religion, seek sacred knowledge, and associate with the righteous.