It is named al-Fatihah
The Opening – because it opens the Book and by it the recitation in prayer commences.
It is also named Ummul Qur’an, the Mother of the Qur’an, and Ummul Kitaab, the Mother of the Book,
according to the opinion of the majority.
The Ruling of Reciting al-Fatihah in Prayer
The opinion of the majority of the scholars, amongst them Maalik, ash-Shaafi`ee and Ahmad, is that it is obligatory to recite al-Fatihah in the prayer and that the prayer is not valid without it.
Their opinion is based upon many proofs; from amongst them the sayings of the Prophet (Peace and Blessings be upon him), “There is no prayer for the one who does not recite the Opening of the Book.” ( Saheeh Bukhaaree )
“Whosoever performs a prayer in which he does not recite the Mother of the Book then it is deficient,
it is deficient, it is deficient, it is incomplete” [Saheeh Muslim ] The prayer is not valid in which the Mother of the Quran is not recited. ( Saheeh Muslim ).
When you stand for pray, say the takbeer and then recite what is easy for you from the Quran. [Saheeh Bukhaaree ].