I am unable to add the image which is saved in my system.
In Ask Question I can add the image but not in the comment section.
Comments do not support the insertion of images. To do that you need to be editing your question (via Ask Question or using the edit button beneath an existing question).
Its the same as for an answer so I'll screenshot this and circle the picture button in red.
To better understand the purpose of comments I recommend reviewing How do comments work? and to understand the Picture button there is How to upload an image to a post? (although the interface is not quite identical to that nowadays).