How to update my iPhone 12 Pro Max iOS 15
I want to update my phone
[Re-Titled by Moderator]
iPhone 12 Pro Max, iOS 14
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.