He served as the Director (Admin) of National Security Intelligence (NSI) and commanded one Infantry Brigade in Bogura.

[8] Shamim was appointed the Director General of Bangladesh Ansar and Village Defense Party on 29 July 2020.

[10] In December 2021, he distributed books written by President Sheikh Mujibur Rahman to officers of Bangladesh Ansar and the Village Defence Party.

[11] As Chairman of Ansar-VDP Unnayan, he handed over Bangladeshi Tk 42.5 million Sheikh Mohammad Salim Ullah, secretary of the Financial Institution Division, to spend on government development programs.

[13] On 6 August 2024, Shamim was appointed Chief of the General Staff of Bangladesh Army following the fall of the Awami League government led by Prime Minister Sheikh Hasina.