Introductory meeting with CFP - what to expect?

I have short-listed three fiduciary fee-only advisor-only CFPs and will be meeting each one of them for the first time.

1. What happens in these first meetings?
2. What are the questions that I should be asking? I already know they are fiduciary fee-only advisor-only CFPs.
3. What are the red flags to watch out for?
4. How long do these first meetings last?
5. Any and all advice is appreciated. TIA.

I ask because one CFP scheduled just a 15-mins call to understand about my relationship expectations with a CFP, the role I expect them to play, etc. while another CFP scheduled a 30-mins call and asked me to submit my net worth statement, statements for the brokerage, retirement accounts and 2023 tax returns!