My iPhone won’t let me update to ios 14

What does your iPhone XR display on the screen when you attempt to update it? Error Message?

Here is good guide published by Apple on How to  ➔ Update your iPhone, iPad, or iPod touch - Apple Support

If you are updating your iPhone over a Wi-Fi Network then-

Make sure that your iPhone is setup to meet the following requirements before you attempt to update the iOS version-

• 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
• If you are not planning for it to update automatically you should turn this option off, as it will only update when the phone is plugged in, connected to Wi-Fi and locked
• 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.