There is a sister in France who a brother wishes to marry. However her father has no religion, and her brother only prays the Jumu’ah prayers?

Shaykh Ṣāliḥ ibn Fawzān al-Fawzān

Is she a Muslim? Is she practising? If she is a Muslim and practising her religion, then her wali (guardian) is the [Muslim] ruler. He is her guardian who marries her off, or the judge in a court. And if she lives in a non-Muslim country, then it is the head of an Islamic Centre, he marries her off if she desires [to marry] that man.