You can have topics view by clicking on ‘Topics’ on the tree in left hand window. Please refer to the IBM Documentation for WebSphere MQ Ver 7.0 for more information about Topics.
Like all other views, you can right click on 'Topics' node and get a popup menu like this.
Click on 'New Topic' to add a new topic.
Once the topic is created, you can right click on that topic to change its 'Properties'.