i am a student working in an simple application and i do not know how to use the img tag and i have tryed one such code but while executing the code the image is not showing
The problem is that you are using an address to an image on your computer, so that will only work when you view the page from that specific computer.
You should copy the image into the web application, for example into a folder named images, then you use that address in the image tag:
images