How do I start an initial conversation with a professor to ask them to let me work in their group as a graduated student
from my experience just last month, I am willing to join a professor's lab in the computer science area, so firstly I did my homework as you did, reading about his staff and paper, etc. then I wrote to him an email with sample subject (student want to work with you) and I explain my background and interests in his field of expertise alongside my CV. after somedays he replies and ask me to do a presentation about some project in my CV, then he asked me to prepare a research proposal and some research question, of course, related to the field. In the end, he accepted me and I am waiting for the acceptance from University research community.
Be confident, professional, and concise in your email. good luck