how update my iPhone to the latest version

Assuming you have a compatible device, see: Update your iPhone, iPad, or iPod touch - Apple Support

And: If your iPhone, iPad, or iPod touch won't update - Apple Support

If the above Apple articles do not help, please post back with relevant information. 

Check compatibility:

Go to Settings/General/About and note the Model Name

• NOTE: iOS 16 is not available for any models except to iOS developers and beta participants. General release will be in Fall, 2022
• iPhone 12 or 13 series: You can update to 15.6
• Any model 6S or newer (including original SE, 2nd and 3rd editions): You can update to 15.6
• iPhone 5S or 6: You cannot update to iOS 13 or higher; you can update only to iOS 12.5.5
• iPhone 5: You can update only to 10.3.4
• iPhone 5C: You can update only to 10.3.3
• iPhone 4S: You can update only to 9.3.6
• iPhone 4: You can update only to 7.1.2

Theweldingdude01 wrote:

Go to settings>general>Software update and it will tell you if updates are available your battery power needs to be above 50% and internet is recommended

Internet access is required to download the update.

Go to settings>general>Software update and it will tell you if updates are available your battery power needs to be above 50% and internet is recommended

Yes absolutely that was my bad thanks

Theweldingdude01 wrote:

Yes absolutely that was my bad thanks

;-)