Change setting update IOS from wifi to data cellular

No. This is because there is no such setting. Your iPhone will use cellular data if there is no Wi-Fi or if the iPhone is not connected to a Wi-Fi Network.

The thing to note is that you cannot perform any iOS updates over a cellular network with your iPhone 8. You must be connected to a Wi-Fi Network to download and complete the iOS update installation.

You may also 👉 update your iPhone by connecting it to a computer and then updating it. The computer, in this case, must have internet access.

Axel F.

You have to just turn OFF the Wi-Fi Setting OR be connected to your cellular network, which you already are.

You need 5G service on your iPhone to install an iOS update over a cellular network. Only iPhone 12 and newer models have 5G capability.

You have an iPhon 8 with LTE cellular service (5G is not available on an iPhone 8) and therefore you will have to update your iPhone over a Wi-Fi Network.

Make sure that your iPhone is setup to meet the following requirements before you attempt to update the iOS version over a Wi-Fi Network. Open Settings ➡️ General ➡️ Software Update: If there is an update available for your iPhone then it will be listed here. Follow the on-screen instructions to download and update your iPhone. 

• Your iPhone must have a fast Wi-Fi connection; you cannot update over cellular data or a cellular hotspot
• The iPhone can not be in Low Power mode
• The battery state of charge must be above 50%
• Your iPhone must have at least 6GB or more free storage space
• Your iPhone cannot be connected through VPN
• You should leave the phone plugged in until it finishes updating, both to assure that it remains above 50% and to keep Wi-Fi enabled (Wi-Fi turns off when the phone sleeps if not connected to power).

Axel F.