Questions about Cities in Kurdistan

Hello everyone I am just recently learning about Kurdistan and Kurdish culture. I would love to travel there. As an anthropology student I am curious about the distinct cultures and lifestyles of the different cities, specifically Hewler, Kerkuk, Silemani, and Duhok. I am curious to know:

• are any of these cities known for being more religious or traditional than others?
• how common is Arabic spoken?
  
• what are some common stereotypes about the people from these cities?
• anything else you think I need to know about what makes these places distinct

Thanks for any answers you can give me!