A Boy and Sungreen(2019)

Original title: 보희와 녹양

Bo-hee, a 14 year old boy, was raised by a single mother and has always thought his father had passed away. Bo-hee hears that his father may be alive, and he sets out in search for him with his best friend Nok-yang. He finds his half sister on the way and forms a friendship with her boyfriend.