The story of helping the local people get rid of the threat. Are there any similar books to recommend? Can you recommend a transmigration novel that tells the story of a doctor on Earth (possibly a genetic doctor) who helps the otherworld to get rid of the threat? I can't remember the name.

His aptitude was not very good. He changed his genes and became a Dragon Bloodline Warrior (not Coiling Dragon). He also had a younger brother inside. He did not like him very much at first, but their relationship became very good later on. That's all I can remember. If you know anything, please tell me. Anxious! Urgent!