I need to update my iPhone

An iPhone 6 cannot be updated past iOS 12.

There are no hardware upgrades available for any iPhone.

Your options for apps that require iOS 13, iOS 14, and the current iOS 15 are an iPhone 6s or newer.

An iPhone 6s has twice the memory of an iPhone 6, among other differences.

Again, iPhone 6 cannot be updated past iOS 12.

First of all, it’s very difficult to read what you’re saying without spaces. Second of all, iPhone 6 can’t be updated. You’re out of luck.