How Can One Become an Immortal Without Elixirs?

Li Bin: "No, didn't you just say that you could use the three flavors of real fire to activate this alchemy furnace?" Dao Gou said with certainty: "Yes, that's right!" Li Bin asked back: "Then why do you still want this from me?" Dao Gou's attitude was sincere: "My three flavors are used to stimulate, and yours is used to fuel combustion." Li Bin: "..." I saw Li Bin with his right hand in the mudra and a solemn expression. Small candle-like flames were lit on the tops of his middle and index fingers. As the wind outside the window blew, the flames made a "pop-pop" sound and might be extinguished at any time. Within an hour, his true fire could no longer hold on, and his body was already too sleepy. He struggled hard and asked: "Curly hair, are you okay? How long will it take?" In the small alchemy furnace, the Taoist dog lay comfortably and whispered to Li Bin outside the furnace: "Seven, seven and forty-nine days."