add extra checkout field

Please read before bid: you will not get ftp access nor admin access, you will get 30 minutes access through Teamview. If you agreed with this then here is the detail: I need to add a extra field in the checkout page of woocommerce, should be easy if you know what are you doing., this field content must be record it to the database for future use. simple as that , more details will give to the winner.