The First Prince with a Different Surname in the Empire

The protagonist travels to a place called the Taisho Dynasty. All three brothers died at the hands of the Huns, and he embarks on a journey to kill the Huns. He was unable to set foot on the battlefield because of his father's orders, but he changed his destiny step by step through business, and eventually became the first person to control the empire's finances. It became the most powerful backing to kill the Huns. His great revenge was avenged, and he started a life of wantonness and freedom. He became the first person in the empire to be crowned king with a different surname.