Does the hadith "We were with the Prophet, may Allah's prayers and peace be upon him, when we were young, fresh youths, so we learned faith before we learned the Qur'an, then we learned the Qur'an and our faith increased thereby" mean that one must learn faith first and then the Qur'an, or can a mature girl combine both?

The aforementioned hadith (definition) was narrated by Ibn Majah and authenticated by Al-Albani. Whoever reaches this age is considered accountable (mukallaf), and the first thing obligatory upon them is to learn the correct creed (aqeedah), as it is the first of the individual obligations (furood al-ayn). Ibn Taymiyyah said: "It is obligatory upon every accountable person to know what Allah has commanded." Al-Akhdari said: "The first thing obligatory upon the accountable person is to rectify their faith." Learning the Qur'an is not obligatory upon every person; rather, it is a communal obligation (furood al-kifayat). However, if it is possible to combine learning faith and learning the Qur'an without delaying the learning of the creed, then there is no harm, due to the saying of the Prophet, peace and blessings be upon him: "The best among you is he who learns the Qur'an and teaches it."