Answer
The answer is as follows. 
Katrielle and the Millionaires' Conspiracy walkthrough
Puzzle Location: The doublée grounds (Flowers gate)
Place the numbers 2, 3 and 7 on the bars of the bird cage to make a bird.
Slide the numbers to move them, and place them on the bars to the right.
You are not making a picture of a bird.
Use the numbers and the vertical lines of the bars together to form letters.
Use the '2' to make an 'R'.
Use the '3' to make a 'B'.
Use the '7' to make a 'D'.
Now you have all the letters you need.
The answer is as follows.