Looking for help using flamegraph on ruby on rails application

Question

I am looking for help on how to use flamegraph in a ruby on rails application. I'd appreciate the opportunity to learn to do this over some chatting service like google meet or zoom(without video just audio and screenshare). If you feel that learning through text chatting or text articles and stackoverflow is a viable as well I am done for that too. I will be more than glad to type up an answer that summarizes all my learnings.