Thank you for using Apple Support Communities! I understand that your location is showing incorrectly on your iPhone 8 Plus. You've come to the right place for help.
Location Services allows apps and websites (including Maps, Camera, Weather, and other apps) to use information from cellular, Wi-Fi, Global Positioning System (GPS) networks, and Bluetooth to determine your approximate location. Let's start by confirming if you have Location Services turned on for specific apps (Including Safari) by following the steps here:
Turn Location Services and GPS on or off on your iPhone, iPad, or iPod touch - Apple Support
Next, let's check if the date, time, and time zone are set correctly on your iPhone 8 Plus. You can check that by going to Settings > General > Date & Time and if possible, use Set Automatically.
If the issue persists after trying those steps, some information that would help isolate the cause of this behavior would be: does this occur when connected to Wi-Fi, cellular data, or both? Does your default location always show as Chicago, IL or does that changed based on location and your network connection?
Take care!