You're kind of on the right track there Mrjimmy.
Open your image in imgHOSTR, select Embed codes and then Full image, BBCode. That will copy the code into your Clipboard - just paste that into your post.
For example, this is the full image
![Click to view larger picture](https://imghostr.net/images/2017/12/15/0aefec470a7725456ebf4fc56cf53c51.jpg)
and this is the thumbnail
![Click to view larger picture](https://imghostr.net/images/2017/12/15/0aefec470a7725456ebf4fc56cf53c51.th.jpg)
To see the differences in the code just click to quote this post and you'll see it all in the reply box.