He was born at Accra cow-lane on Apri 23, 1919 by reputable parents from a well cultured and knowledgeable House.
His father, Sheikh Imam Nuhu Sharubutu was the Imam-Raatib (regular or residential Imam) of the Accra Central Mosque in the late 1960s to 1982 when he demised.
His mother, Hajja Ayishatu Abbass popularly known as Mma Tasidi, may her soul rest in peace and perfect bliss, also contributed immensely to the moral and psychological development of her son by ensuring that he had the proper home upbringing to go side with Islamic Education.
In 1974, after lengthy discussions among the traditional and tribal chiefs, academics, Islamic scholars, and religious personalities, a consensus was reached for Sheikh Osmanu to be appointed as the Deputy Regional Chief Imam of Ghana, deputising his cousin, Sheikh Imam Muhammed Mukhtar Abbas who succeeded his father.
The appointment of Sheikh Osmanu as deputy Greater Accra Region Chief Imam was done in consideration of the unique qualities, Intellectual capacity, dedication to teaching and passion for Islam and exemplary lifestyle in him, but he turned down their offer which was forced on him by the Prominent Muslim Chiefs who persistently asked him to give it a serious thought stressing to him that it could be a divine call to serve God.
Subsequently, when it dawned on Sheikh Osmanu that it was a divine call for him to serve Islam and Muslim communities, he finally accepted the position as the acting Greater Accra Regional Chief Imam until 1993, when he was ceremoniously appointed as the National Chief Imam of Ghana to head the Ghanaian Muslim Communities.
Last year on Sunday, 21 April 2019, the Chief Imam joined a mass service at the Christ the King Catholic Church in Accra to mark his 100th birthday anniversary.