Answer 1

Yes, you can surely. But it's not that popular nowadays. Try referring to these links once.
https://www.quora.com/Is-C++-a-suitable-language-for-back-end-web-development
https://softwareengineering.stackexchange.com/questions/53624/can-c-be-used-as-a-server-side-web-development-language
https://stackoverflow.com/questions/22258589/c-on-the-back-end-of-web-app