Is it possible to have 2 iPhones connected to 1 iCloud account?

Hi everyone! Hoping to get some clarification regarding having 1 iCloud with 2 iPhones connected to the account & how the sharing of photos works because I'm finding it to be very confusing!

Long story short, I'm wanting to delete some photos off iPhone #2 that were originally taken on iPhone #1 to clear up space as I'm getting short on iPhone storage. I still have access to the original photos on iPhone #1.

If I delete these photos off iPhone #2 am I going to lose the originals too though? The first iPhone doesn't have a sim anymore nor is it connected to wifi, but I can still access it.

Thanks so much

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