Besides adding one single task in the tasks list from your project, you also have the possibility of inserting multiple tasks at a time.
To achieve this, select multiple consecutive rows using either CTRL or SHIFT keys on your keyboard and then click on Insert option from the Task menu, or press on Insert key or use the New Task option from the contextual menu to insert multiple tasks at a time. These tasks will be positioned above the selected rows in the tasks list.
The number of newly inserted tasks will be equal to the number of selected rows. The remaining tasks will have their IDs automatically renumbered.
All the Inserted tasks will have "<New Task >" as name and duration of 1 day?.
Select a group of four tasks in the task grid using the SHIFT key for multiple selection. As you can see below, the selected rows are highlighted with blue background.
Then right click on a task ID belonging to the multiple selection, and from the contextual menu choose New Task option.
As a result, four new tasks will be inserted at the same time above the task with ID = 27 (Rough grade site (cut and fill)) - in the above printscreen, and the below tasks will have their IDs renumbered.