How RGB images are formed I have a noob level question about RGB images-
Pixels in RGB images are in the range of (0-255), so technically each channel ranges from 0(black) to 1(white), then why we say that each image has a Red, Green, Blue channel component, although they are only Gray channel. In short, how the image is formed?
Each channel ranges not from black to white, but from off to full intensity. What colour is meant by full intensity is down to convention and the presentation technology.

For example, a given image file format might say there are three bytes, of which the first is the red channel, the second is the green channel, and the third is the blue channel. There are many different colours, so to be a real standard, it has to say exactly what that "red" means, usually by reference to a particular colour standard such as sRGB or CIELAB. These international standards provide an absolute way to describe colours.

After some processing, your red, green, and blue values find their way to your LCD monitor. There, the electronics uses them to control the intensity of three sub-pixels: one of which is a red filter, one a green filter, and one a blue filter. The 0-255 value in the red channel is turned into some voltage which controls the transparency of the liquid crystal behind the red filter, turning it from completely opaque at 0 to lets all light through at 255. Since this is attached to a red filter, it contributes black or red to the image.

The same idea is everywhere in computers. The only things inside a computer are numbers. They only mean what we say they mean because of conventions (all software interprets them the same way) and/or because they control some values inside some output hardware. e.g. one number means the red channel in a pixel on your screen, another number means a letter of the alphabet in an email, another number is a pressure sample in an audio file which will be sent to your sound card and control the voltage to a speaker, and so on.