I am new here. I need A - Z Briefing about using adobe firefly beta.

One of the things about betas is that they are released for testing - both technical testing and to test the people who might use it. This usually means they are released before detailed manuals are made, and before tutorials and videos are made. It also means there aren't a whole lot of experts on it already. So, you aren't likely to get a step by step guide while it's a beta. It's there for you to play with and try to get working. If you can't figure it out, that's valuable feedback for the beta team, so let them know.