Final answer:
The question refers to a common action in many computer applications where objects can be manipulated. To perform this task, you click and drag the mouse cursor to create a selection box that encompasses the structure you wish to select.
Step-by-step explanation:
The question seems to be referring to an action that is typically performed in a digital environment, such as a computer software application. When asked to select the entire structure by clicking and dragging the green box around the structure, you're likely working within a program where structures can be selected, such as a graphic design software, a computer-aided design (CAD) program, or any other application where objects can be manipulated.
In order to carry out this task, you would use your mouse cursor to click at one corner of the structure you wish to select. Then, while holding down the mouse button, drag the cursor diagonally across to the opposite corner of the structure. This action should create a green box, also known as a selection box, which expands as you drag. Once the box encompasses the entire structure you want to select, release the mouse button. The structure should now be highlighted or otherwise indicated as selected within the software.