A Muslim should read the Qur’an and reflect on its meanings so as to translate its teachings into practice. The story of Maryam is full of lessons a Muslim has to learn such as putting one’s trust on Allah, Allah’s help to his true servants, etc.
As for the Qur’anic verse you cited, Ibn kathir in his well-kown Tafsir states the following:
(O sister of Harun!) refers to the brother of Musa, because she was of his descendants. This is similar to the saying, `O brother of Tamim,’ to one who is from the Tamimi tribe, and `O brother of Mudar,’ to one who is from the Mudari tribe. It has also been said that she was related to a righteous man among them whose name was Harun and she was comparable to him in her abstinence and worship.
All in all, the above information is not among the basics of belief, and there is a difference among scholars regarding who was “Harun” referred to in this Qur’anic verse.