Miftah
No. Miftah is an Arabic common noun used as a given name but it is not the proper name of any person mentioned in the Quran.
Literally it means 'key' or 'that which opens' (Arabic: مفتاح).
Yes. Miftah is attested historically and in modern usage among Muslims in South Asia and Malay-speaking areas, sometimes in compound names like Miftah-ud-Din.
Yes. It is a meaningful Arabic word with positive connotations and is commonly used as a Muslim given name.
Miftah is primarily masculine; feminine adaptations are rare but compounds or feminine appellations can be formed culturally rather than as classical Arabic feminine nouns.