There are multiple ways to create a new task. Go in the folders tree view and select the folder where the task will be located. All the tasks for this folder will be displayed on the list situated on the right side of the folders tree.
Then you can do the following:
1. Right click on the tasks list and choose the New option from the displayed popup menu.
or,
2. Click the New button on the toolbar (this is the first button on the toolbar)
or,
3. Go to File menu and choose the New Item option.
or,
4. Go to the Tasks menu and choose the New option.
The newly created task will be displayed in a new window and you can edit/view it.

If you specify the due date for a task, then an event will be created in Task Due Dates folder.