Link tasks in your project
Most projects aren’t just a list of completely independent tasks. Usually a project has some tasks that can’t start until other tasks have finished. In Project Web App, creating this kind of a relationship between tasks is called “linking” the tasks.
To link tasks in Project Web App, simply select the tasks you want to link, and then press Ctrl+F2, or click Link Tasks in the Editing group on the Task tab.
The order in which the selected tasks are linked depends on how you selected them:
To link tasks in a specific order, press Ctrl and then click each individual task in the order that you want them linked. Then press Ctrl+F2, or click Link Tasks in the Editing group on the Task tab.
To link consecutive tasks in the order that they are listed in your project, click a task, press Shift, and then click another task. The two tasks that you clicked, and all tasks that fall between them in the list, are selected. You can also click the row header and drag up or down to select consecutive tasks for linking. Then press Ctrl+F2, or click Link Tasks in the Editing group on the Task tab.
If you no longer want your tasks linked, you can remove a link at any time. To remove task links, select the tasks that you no longer want linked, and then press Ctrl+Shift+F2, or click Unlink Tasks in the Editing group on the Task tab.