how do i share a image when i post a question
can't do it at this web site
You can, however, post a link to the image. Usually, this web site does not allow postings of URL's, but if you leave off the initial string up through the colon slash-slash then you can sneak it by the detection algorithm.
If the image file is local to your computer, there are various places that allow you to upload your image, such as imgur and others. Then you can post the URL.