Late Yuan Dynasty: from Bandit to Hero

Traveling through the late Yuan Dynasty, I became the useless third boss of the bandit village. Use reagents to identify poisons, use blueprints to build cities, and use chemical formulas to create "demon fire" to repel the vanguard of the Red Turban Army. Everyone in the world thinks that I have inherited the inheritance of an immortal. Only I know that this is nothing more than a dimensionality-reducing blow from modern knowledge. Collect refugees, reclaim wasteland, refine steel, and store firearms. The down-and-out princess is at my disposal, a wealthy businessman from the south of the Yangtze River has made a bet on investment, and a female general from an enemy country has defected to me. When I am sitting on a hundred thousand cavalry, I am approaching the capital city. Emperor Yuan on the dragon throne asked in a hissing voice: "What exactly do you want?" I unfolded a red flag with the ultimate task issued by the system written on it: [The sun and moon reopen, Han family's sky]