yes you can and you use the image tags to do it.
However you need to upload the image to a server somewhere, if you have your own website then you can have a page just for that purpose. If you dont then most isp's now give some free webspace with your account so you could utilise that.
You then need to put the entire url of the image inside the image tags:
It's worth adding for future reference, that there is a separate YBW forum "Web News & Feedback", accessible from the main index, for questions about using the forums.