From the Work Breakdown Structure page, click Enable Edit from the Actions menu or page toolbar.
For a project template, the Edit WBS page opens. For a project or task, the page toggles to Edit mode.
If the task you want to add a task under isn't visible, use the page expand or filter tools to display it.
To add or insert projects, select the needed option from the page Actions menu or toolbar:
Insert Existing Project Above. Inserts a subproject above the selected task/project in the structure, as a sibling.
Add Existing Project Below. Adds a child subproject to the selected task/project.
If you are not a Project Lead, you can only add projects as subtasks to your assigned tasks. You cannot add siblings for your assigned tasks.
Check the projects you want to insert or add. See Choosing Items by Selecting from a List.
Click Next. The project(s) are added to the WBS as tasks.