@creativegoat Hi there! If you've come directly from the course lessons, you don't see the "New Topic" button because you are already inside a post thread. In order to come out of your current thread, you can click on one of the parent categories listed on the top, which shows your location in the forum category structure.
For example, the "Home" on the top of this page will take you to the set of main categories:
If you get out of your current thread and into a parent category (and any parent category will do), then you will see the "New Topic" button either at the bottom of the list of main categories, or at the top preceding the list of topics in a given category.
I hope this helps, and, if you're new to the forum, then a very big welcome to you! I hope you find this a useful and fun place!