Yes, you can but be aware that deleting a lead means the lead details are permanently removed, so it should only be done in rare circumstances such as a duplication or spam lead. If you've been unable to get hold of a lead, or they are no longer interested in treatment, you need to mark them as 'inactive', which is different to a deletion.

To delete a duplicate or spam lead:

Step 1.
Open the dashboard task.

Step 2.
Click 'Delete' in the top right of the task.

Step 3.
Select a reason for the deletion.

Step 4.
Click 'Delete'.

The task will be removed from the dashboard.