A Gift of 300,000 Yuan Turned Me into a Women's Clothing Boss

My name is Wu Xingchen, I am 24 years old this year. Because I urgently needed 300,000 yuan in medical expenses to save my girlfriend, I had no choice but to put on women's clothing and go on a blind date, and married the 36-year-old bachelor Zhao Dawei. I originally wanted to earn enough money to pay back 300,000 to Zhao Dawei and confess that I am a man. But at this time, my girlfriend was told that she would not be able to have children due to the impact of the surgery. At that time, my sister, who was married far away, secretly gave birth to a son and gave it to me to raise, and said that this would be my and my girlfriend's child from now on. This matter was discovered by Zhao Dawei. He told me that he could not have children either, but he was afraid that men would be laughed at by others for being infertile and that no one would take care of him in the future. He asked me to give him my son, and he would not want the 300,000 yuan gift. Or let me continue to pretend to be his wife and raise this child together, and I don't have to pay back the 300,000 yuan. What should I do?