my iphone says it is unable to update to ios 13

Get help with iOS updates

https://support.apple.com/en-us/HT209571

Get help with over-the-air iOS updates

https://support.apple.com/en-us/HT201435

Get help with iOS update and restore errors

https://support.apple.com/en-us/HT204770

Try to update with iTunes on a computer.

I have a 6 and can't get past 12.2.3

Vinstar1 wrote:

I have a 6 and can't get past 12.2.3

That's true. A 6 cannot be updated to iOS 13.