I am new to publishing the google app. I am planning to publish a google sheet app. How does billing and licensing work here. Do we need to have our own billing server. I am not quiet clear on this. Please help to know the working of licensing and billing server

I read through workspace document on publishing app. But didnt get a good picture on billing and licensing.

Some high level walkthrough on process, let say once I publish my app. How do I can track who downloaded, licensing applied to users, tracking revenue, expiration etc. Where I can view and track these information for all downloads and usage.

Some pointers would be helpful.
Thanks
HK