Order Status change from processing to compelete

I have a question ?

In my website I have been using Learn dash for selling course. When ever any one orders it by default the order status will be in processing in orders list. Is there any way I can make the orders status to completed once the customers had done the payment.

Like : If a customer buy a course and post payment is done the status should be changed to complete rather then processing.

Any ideas how can I can do that.