Imperial Examination? Dogs Don't Even Take the Test! I Relied on People to Set Me up as Prime Minister

Before time travel, the protagonist was a gold medal personality planner in the entertainment industry, specializing in creating "personality labels" for artists and manipulating public opinion. After traveling through time, he discovered that "fame" in ancient society was the hardest currency. It takes several generations to accumulate the reputation of a wealthy family, but he can use modern public relations methods to complete it within a year.