My org VP holds office hours every week. Also he sometimes does AMA sessions. I'm usually not sure what to ask so I don't avail those sessions as I don't want to ask any stupid questions.
This really depends on the person... but in my opinion AMAs are places where you could ask some questions that are a bit of curveball and not really a tactical thing related to the current set of priorities. I feel like these questions give valuable insights into how the person thinks.
I recommend going through the linked resources in the description of that video as well!
...as I don't want to ask any stupid questions.
Don't worry about looking "stupid" - As long as the question comes from a good place and you ask it politely, there's no harm done and only potential upside. If you're relatively new to the company, you can also attach a preface like "I'm new here so apologies if this is a dumb question, but I was just curious about...". When you preemptively put that self-deprecation "shield" in place, it's really hard for the other party to be mean to you in response. I talk more about this communication tactic here: "How do you overcome the fear of asking stupid questions / bothering people when you need help?"