@Snoelle_Fitzshine if it's a Mac, do it like this:
Click the bar where you type in website addresses. It should become highlighted automatically. Then hit the keys command and C at the same time. That tells the Mac to copy. Go back to your post, and click in the editor so the cursor (flashing bar thingy) appears where you want the link to go. Click command + V, and it will be pasted after the cursor! 
Hope that helps!
