First open the game and click to enter the Seventh Courtyard;
Click on the screen in the new interface to start the file story;
Get the key at the upper right side of the operating room and use the key to open the cabinet door;
Then get a new paper clue;
Obtain the password and open the lockbox according to the clues on the paper;
Finally, after getting the key from the lock box, you can directly open the door of the operating room and go out.