You need forum trust lvl 3 to post such images. But you can post link: type the link, select it with mouse and press </> (preformatted text) button and you link shows like this:
https://worldofwarcraft.com/en-us/
Then people can copy and paste it to see your image. Trust lvl 3 people can also then repost to full image for you.
You can see here how you can gain trust lvl 3.
Basically shortly it requires to visit forums very regulary, write and reply to lot of posts, read LOT of posts and not be banned (for writing bad stuff etc.) for certain time.