Peffers. War Child, #0.5

Peffers by C. P. Clarke is a military action novel that serves as a prequel to War Child. It follows Robert Peffers, a young soldier who rises through the ranks to become a captain. The story begins with Peffers' difficult childhood, marked by bullying and a life-changing decision to join the army. Over time, he evolves into a highly skilled and disciplined soldier, taking on increasingly dangerous missions, including clandestine operations for the CIA.
The novel details his rigorous training, overseas deployments, and moral struggles as he transforms from an insecure boy into a hardened warrior.