Do expats visit (hang out at) certain persons in Erbil?
Do you mean places? If so, yes there are places. Try the village of Ainkawa attached to Erbil. There are eateries around there with a mix of expat and locals. Eateries for expats charge around $20USD for a meal not including drinks. It is double what the locals pay in local places. Eating at the two major mall food courts on Friday or Saturday will also help you meet expats. That is Majidi Mall and Family Mall.
Is English used in most of the modern stores?
At Majidi Mall Hypermarket (Called City Center Supermarket) the support staff is all from India and they speak English very well.
At Family Mall Carrefour Hypermarket the managers speak English and French
At other stores only Kurdish is spoken. Sometimes Arabic or a language similar to Turkish called Turkmen.
I have had difficulties trying to shop in neighborhoods ranging from merchants charging me bigger prices to hostile stares from locals, to harassment from men. I gave up shopping in neighborhoods. Maybe if you live in the neighborhood and shop there it is no problem? Ainkawa is fine, all of Ainkawa is fine and no one took advantage of me there.
I do tend to do all of my shopping at Family Mall or Majidi Mall. I love the fruits and veggies at Majidi mall. Summer time fruits and veg look shabby all over due to extreme heat so be prepared. Rest of the year it is lovely.
Be sure to go to a falafel stand. Delicious and cheap meal all over town. Runs 500 dinar to 750 per sandwich. Don't get the cut veggies on it as they may make you sick. That is my favorite lunch here as I am vegetarian.
Is there an organic store there?
I wish. I do so wish.
Some limited organic products (mostly shelf stable like brown rice, Non-GMO soya protein etc.) can be found at Tableau Mall in the grocery store in the basement. I have not seen any organic fruits or veggies.
There seems to be some difficulty with the supply chain for international foods here. For example peanut butter. You will suddenly see it in the store and then it will be gone for 6 months. Cereal, candy and cookies are always in stock. The few organic shelf products at Tableau mall also come into stock and then disappear for many months before returning.
Buy household items in small fixed price stores. There are some stores in different places that sell items for 1000, 2000, and 3000 ID. Will be a lot cheaper than the malls. Find a taxi driver who knows where these are.
Used clothing and household items market at a place called /Lang Uh/. All stuff sold off in bulk by charity/thrift stores in USA and Western Europe. Then it is brought here and sold by the piece. Market is closed at the 5 prayer times. Very busy on nonworking days. Best time to go is 4pm in the evening. Take small bills with you like 1000 and 5000 for paying.