Desktop Sharing Tool / Desktop Monitoring

Hi out there, we want to start a new software tool but don't know how to deal with it and how much it might cost. Therefore we are looking for an experienced developer. I will devide it in to 2 mainparts with options. Please be so kind and make your vaguely offer with and without those options. My description is for now very open, a more detailed version will be written down if we know in which range move. Part 1 - Desktop Sharing Tool / Desktop Monitoring Desktop sharing with the ability to change the viewing direction Option 1 cross-platform (Linux, MacOS, Win) Option 2 cross-platform (Android, iOS) Part 2 - Streaming of desktop to video media (e.g. website) The possibility to stream your content to a website and the website might be viewed by more participants