Arrange your content in hierarchic view
The root item is the project/solution (solution is a spacial project that can contain child projects. Usually used to map your product)
Under a project – you would usually add Document item types, and underneath a document, you will add a paragraph
Under each paragraph, you will add the relevant work item, such as System requirement, software requirement, test case, etc.
Selecting any work item on the tree will show its details on the right side, separated by tabs.