How do I simply send iphone photos to another iphone?

The simplest way is AirDrop.

You can read how to send and receive with AirDrop here:

https://support.apple.com/guide/iphone/use-airdrop-to-send-items-iphcd8b9f0af/ios

leandra ~ You could create your own custom shortcut with Apple's Shortcuts app:

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Smart solution.

leandra ~ I just noticed that you're running iOS 10 and your iPhone 5c can't run iOS 12 or later required to use Shortcuts app. – Sorry for the confusion!

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