Photos in iCloud

Personally I prefer to use iCloud Photos. See: Set up and use iCloud Photos - Apple Support

When using that, after allowing time for all of the photos to sync with iCloud you can use an internet browser and log into www.icloud.com and go to the Photos app there and verify that all of the photos have synced -- there is a total photo number at the bottom of the screen on iCloud.com and on your device.

When you get a new phone, if you turn on iCloud Photos on it, the photos will sync to it.

If you have iCloud Photos on and then do an iCloud Backup, the photos will not be included in the backup since they are already on iCloud.

Also note that iCloud Photos is a syncing service. Any photo you delete from a device where iCloud Photos is turned on will also be deleted from iCloud and from any other device connected to iCloud Photos. You can potentially reduce the storage space required on a device by turning on Optimize Storage.

If you are no longer using the phone, don't turn off iCloud Photos on it. Do the following: What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support That procedure will not affect your iCloud Photos or anything else on iCloud.

If you decide to turn off iCloud Photos for some other reason, see the "How do I turn off iCloud Photos on only one device?" section and the "How do I remove all iCloud Photos content from iCloud and my devices?" section of Get help with iCloud Photos - Apple Support

Can you clarify why you want to turn off iCloud Photos on your phone?

If you are asking about the old phone that you will no longer use, see the following from my previous reply:

If you are no longer using the phone, don't turn off iCloud Photos on it. Do the following: What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support That procedure will not affect your iCloud Photos or anything else on iCloud.

Hi. If I turn on the icloud photos on my iphone (its the only apple device i have) and reset my phone to buy a new one, won’t my pictures be lost from icloud since im technically deleting them from the phone when I reset it?

And whats happens to the photos if i decide to turn the icloud photos off?

Thank you for your reply. I read both links you sent but I still don’t quite understand if my pictures are still on icloud after I turn off the icloud photos on my iphone. I understand that if I have another apple device, I would still be able to access the photos on icloud photos if that is still turned on on this other device. But since I only have an iPhone, would they remain saved on icloud for me to access through icloud.com or would they only be saved on my iphone storage?

They should transfer if you only do a backup.

I prefer the iCloud Photos method because I can verify that they are actually on iCloud which cannot be done with just iCloud Backup.