Angdembe campaigned for multiparty democracy during a referendum in 2036 BS. He got affiliated with Nepal Students Union in 2046 BS and was actively involved in the first people's movement.
Angdembe worked as a central member of the student wing twice from 2046 BS to 2052 BS. He then took over the responsibility of central vice-president of Tarun Dal after entering as a central member in 2054 BS. Angdembe got elected Nepali Congress central committee member thrice through the eleventh, twelfth and thirteenth general convections.
He was elected Constituent Assembly member from Panchthar-2 in elections held in 2070 and severed as Chairman of the Industry, Commerce, Labour and Consumer Interest Committee of the Constituent Assembly.
Angdembe took over the responsibility of the coordinator of the central disciplinary committee of Congress in 2077 BS. He got elected Joint General Secretary of the party through a general convention held in 2078 BS.
He was Elected Constituent Assembly member from Panchthar-2 in elections held in 2070 BS.