Prohibit screenshot: My company info is critical that we did not want our users to screenshot and share amongst others. Please advise if you know a software for iOS.

What if they point a camera at the screen and take a photograph/video?

You'd have to set up an MDM solution that includes the ability to disable screen captures, and install an MDM profile on each device. Not sure if Apple's MDM product (Profile Manager, included with macOS Server) can do this or not.

However, as pmills posted, if someone really wants a picture of the screen, they can easily use another device's camera.