Live streaming video services

[Shakthi Sachintha]

I want to create a video streaming service that some registered users can create live streams on the website and only authorized users can view them. I couldn't find any suitable streaming service to achieve this. can somebody suggest me a live streaming service to achieve this task? there can be many live streams at once.
I have no idea how live streams work in the backend if someone can guide me how they work it would be a great help. thank you...