How do I delete pictures from my phone but not my icloud?

jozalyn254 wrote:

I would like keep pictured from my camera roll on my icloud but I would like to delete some of them as some are at least 3 years old. Is there a way to do this?

iCloud Photo Library - Apple Support

No.

You can't do that because iCloud is used to sync data between devices. So if data is deleted, it is deleted everywhere including iCloud.