Create multiple Order line items using Salesforce Lightning component

Lightning component display a list of all existing orders. We have a '+' button the screen. When user hits the '+' but it open popup modal where user will select Order values. There is another  "+" button on the same lightning. When click on '+' which is displayed on popup box, user will be able to create a new row where user  will selects the product name, automatically its description and unit price gets populated. User will enter quantity value. When hit on save it will create Order and its line items.