How can we make an image to be responsive?

Making images responsive with CSS is actually very simple. You just need to add these properties to an image:

img {
  max-width: 100%;
  height: auto;
}

The max-width of 100% will make sure the image is never wider than the container it is in, and the height of auto will make the image keep its original aspect ratio.

Source: https://www.freecodecamp.org/learn/responsive-web-design/responsive-web-design-principles/make-an-image-responsive