Wanna updates my phone

See Update your iPhone, iPad, or iPod touch https://support.apple.com/en-us/HT204204 and the related compatibility guides below.

iOS 13 and iPadOS are compatible with these devices - Apple Support.  

iOS 12 is compatible with these devices.

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And, if pertinent see If you see an error when you update or restore your iPhone, iPad, or iPod https://support.apple.com/en-us/HT201210 and

iOS update and restore errors https://support.apple.com/en-us/HT204770. 

Get help with over-the-air iOS updates          

Have you tried using iTunes on a computer or Finder if running Catalina to do the update?

 Update software on iOS devices in iTunes on Mac