Running a C++ code written for Windows on Amazon Web Service

I am new to this website and this is a general question that I know many people want to know:

I am a C++ Windows Software developer, my customers are supposed to buy my software and install on their computers. the software is supposed to send the results by Ftp, Http or any better way (you suggest if any) to their reserved space on Amazon Web Service. then they should be able to login and see those results (that are processed on the server by another C++ software, I name it 'Server side C++ code') by a web GUI.

'Server side C++ code' should only be written in C++ and for Windows , not another language or operating system. I mean I want it to be run on a windows server.

My questions are:

1) Can I use Amazon Web Service for this purpose? if yes which service, and if no what Service is possible?

2) which protocol is better for sending the results? Ftp/Http? or what? (if you are not sure please just answer my first question)

Thank you very much for helping me.