Cong Jintian Kaishi Yang Long

Ling Enping wanted to prove his father's innocence and bring his family back to prominence, but he had no magical abilities to do so, until one day when he accidentally triggered the Dragon Farming System. Suddenly, he became a talented magician, the most powerful mage in the empire took him on as an apprentice, the king made him a duke, and he even became engaged to the princess. But amidst all the accolades lurked many hidden dangers, and even the System that helped awaken his talent was hiding a conspiracy of its own...

(Source: Kuaikan, translated)