iOS 11.0.2 - AirDrop not showing up in Control Center even after long pressing the "Network Icon Group" in the Control Center
I am using an iPhone SE and a long press on the network settings box in the control center is working fine for me. 

If the box opens but there is still no icon, you can check if there are any restrictions active like in the article mentioned by Melvin Jefferson (found in settings / general / restrictions).