If I delete photos and videos that are in attachments on my Iphone, will they delete from my iCloud photos?

Hi JenAiple,

Welcome to Apple Support Communities! We appreciate you reaching out for help with this question. We're glad to help.

To ensure we understand correctly, it sounds like you're asking if deleting photos and videos that are attachments in the Message app or Mail app will also delete them from your Photos app, and therefore from your iCloud Photos. Is this correct?

If so, you can rest assured. So long as the attachments have previously been saved to your Photos app, deleting the attachments will not remove them from the Photos app.

Here's a guide with more information:

Use Messages on your iPhone, iPad, or iPod touch - Apple Support

We're here for you if you've got any questions.

Have a great day!