Function of optical filter

Filters have played a great role. Widely used in photography. Why is the main scene always so prominent in the landscape paintings taken by some photographers? How do you do it? That's what filters are for. For example, if you want to shoot a yellow flower with a camera, the background is blue sky and green leaves. If you shoot according to the routine, you can't highlight the theme of "yellow flower" because the image of yellow flower is not prominent enough. However, if you put a yellow filter in front of the camera to block some green light scattered by green leaves and blue light scattered by blue sky, and a large number of yellow light scattered by yellow flowers pass through, the yellow flowers will be very obvious, highlighting the theme of "yellow flowers".