Currently working on a project that uses LabVIEW Interface for Arduino and from my knowledge and research the Vin from the USB port to Arduino is 5V so i was wondering how am i able to display and prove that it's 5V on LabVIEW? Please enlighten me if i'm wrong about the voltage being 5V.
First thing - USB is designed to provide 5v. It is very reliable technology. I would not feel any need to check it.
If you must check it you are faced with the problem of the ADC measuring the voltage it uses as a reference - can't be done directly. I think you could use the internal 1.1v ADC reference voltage together with a voltage divider that steps the 5v down below 1.1v
You will also face an interesting challenge to prove that your system works.