Write some Software

I have a website that need some modification. On the invoice screen, add a button to "Pay Cash" for online orders but customer will come to the store to pay cash to the cashier. The button should only appear for customers that are assigned login IDs and passwords. The online order will have to be save under a confirmation number. The customer will enter his/her phone number/name for later retrieval by the cashier in the store so the order can be processed or paid. Look at [login to view URL] and see if u can do this project.