You can delete items in two ways.
Right-click on any item and select Delete item, or
drag your item to the Deleted items trash can on the left side of the project view in order to delete.
Deleted items are removed from all lists and projects.
To view your deleted items, click on Deleted items.
To restore a deleted item, right-click on it in Deleted items. Then click Restore item. To permanently delete, right-click on the item and then click Permanently delete.
To permanently delete all of your deleted items, right-click on Deleted items and select Permanently delete.