Sangma was born on 20 April 1965,[1] son of teachers Binoy Bhushan M. Marak and Roshanara Begum at Ampatigiri, now the headquarters of South West Garo Hills district.

[10] Sangma was named as one of the candidates for the 2018 Assembly elections in Meghalaya, contesting seats from the Songsak and Ampati constituencies in which he won from both.

[14] Sangma has launched multiple social assistance programmes, including the Special Wedding Assistance Scheme for orphaned girls over the age of 18[15] and a programme for providing aid to single mothers and orphaned girls.

[16] In 2017, Sangma launched the Life Programme (Livelihood Intervention and Facilitation of Entrepreneurship), aimed towards empowering people for economic prosperity.

[21] In 2018, he launched a Career Guidance Program to offer specialized coaching support for underprivileged students.