After clicking the "image icon" (img)(/img) you must then (copy/paste) the URL of the image you want.
This URL (the "
http://www.etc stuff) can be from someone's Internet web site (after determining whether or not it's copyrighted) or from your own web page. Some sites block outside linking, so it's best to check before putting a lot of work into this.
There are sites (image hosting web pages) where you can upload your own private images and then link to them. I think if you do a SEARCH you can find plenty who are willing to lease you space on their servers (perhaps even a few "free" ones).
It's best to try this with a single image as a test... then wait a day or two to see if you can still view it when you return visit. If so start posting.....
You should (by now) have checked the Forum Rules and Help to see if you can find better guidance than this quick little "how to" ...... I don't think this board has restrictions on which picture hosts you can use.... but I could be wrong about that - several others do limit you to certain ones!
Good luck