There are two ways to create a task in Board view:
1 Hover over the corresponding column and click the "+" sign.
2 Click on Add a task at the bottom of the column.
This will open a field 3 where you can enter the task name.
After that, a task card with some default data will appear. You can then edit this data directly from the card or by opening Task settings.
The new task will be added at the end of the column and shown at the end of the WBS (Work Breakdown Structure) as a single task. This is the default rule that applies to tasks you create as well as those created by other project participants on the Board.
There is also a possibility to quickly view overdue tasks in the Board view. Click on the corresponding icon 1 in the top left corner. Cards with overdue tasks will be highlighted in red 2.