Complex sentence: His father Tarkanta Dasgupta was a doctor with the Indian Railway, thus he spent early part of childhood travelling to numerous places, it was only at the age of twelve that he was sent to Calcutta to study at Dinabandhu School, Howrah.
Split into simpler sentences: His father Tarkanta Dasgupta was a doctor with the Indian Railway, thus he spent early part of childhood traveling. It was only at the age of twelve that he was sent to Calcutta to study at Dinabandhu School, Howrah.