Validate Address with SmartyStreets API

Hello, I want customers to submit Verified Addresses in Checkout. Currently user just enters manually into fields. I'd like switch to verified emails. The way I want to do this is the way its done on this website: [login to view URL] User types address in 1 field , it validates against USA database, and then populates rest of fields above Street Address field in my checkout, so user doesn't need to move fields to type address, just types it in all in 1, and then once they choose the verified address that comes in dropdown, it then auto populates the below fields.