How to Set Up a Task List in SharePoint 2013
Click the Settings gear icon.
Select Add an App.
Click the Tasks app.
You can find the Tasks app in the list of templates.
Enter a name for the Tasks app in the Name text box and then click Create.
In this case, the app is called My Tasks.
The new My Tasks app appears in the Recent section of the current navigation.
It also appears in the Site Contents page.
Click the app to open it.
Then click the New Task button to begin creating tasks.