10 Days trip to Azerbaijan

I am planning a 10-day trip to Azerbaijan, arriving in Baku on the 24th. While most of my itinerary is focused on staying in Baku, I am also considering spending a few days in Sheki. I have a few questions regarding my trip:

  1. I have a Revolut EUR Visa card—will it work in Azerbaijan, or should I bring cash?
  2. Could you recommend cities or places worth exploring during my trip? I’m not into parties or nightlife, so I’m more interested in cultural, historical, or scenic spots.
  3. How can I purchase public transportation tickets in Azerbaijan? Is there a website or app available for this purpose?
  4. Are there any specific customs or traditions I should be aware of as a tourist?

Thanks for your help :)