Excuse me, what is F11 aperture and what is F8 aperture? (Please explain with pictures)

In layman's terms, the aperture is a hole with adjustable size on a camera, and the aperture can be adjusted by adjusting the blade, so as to control the amount of light entering.

Look at the figure below, which shows the aperture size under various aperture values. It can be seen that F11 is smaller than F8. Its light intake is double, that is, the area is half smaller.