Customers visiting your store place orders to buy your products. When they place a new order, it will be automatically updated on your store. You can view this on your dashboard in 'Orders Received' box, which is one of the six boxes on your dashboard (see screenshot below). When you click the box, the details of the orders will be displayed.
You can also view newly placed orders in 'Manage orders' of 'Business' section on your dashboard. By clicking 'New Orders Received' you can view the details of the new orders in a page as shown below. The details of the customer who placed the order can be seen by clicking 'view' option along every order as show below.
After checking the customer and product details, you can approve or cancel the order by clicking 'Approve' button or 'Cancel' button respectively. It is shown below. If you approve the order, then the process moves on to packing.