Can I delete photos on my phone when it’s on iCloud on my laptop?

Is your iPhone signed into iCloud Photos? And your laptop as well?

As tygb explained, iCloud Photos is not a separate external storage, it is a syncing service. To put it slightly differently - the purpose of iCloud Photos is to keep the photos library on the synced devices identical. You will always see the same photos on all synced devices as in iCloud.

You must not delete a photo from a synced device, if you want to keep it in icloud and your other synced devices.

• If your iPhone is running out of storage, use the option "Optimize iPhone Storage" in the Setting > Your Name > iCloud > Photos. Then the iPhone will store less full sized originals locally. But do not delete photos you want to keep.
• If "Optimize iPhone Storage" does not suffice to free enough storage, move photos out of your iCloud Photos Library. Save the photos, that you do not really need on the iPhone in your iCloud Photos Library but save them on your Computer elsewhere. The device with the smallest storage should determine how large you will let your iCloud Photos Library grow.

Hey Yo_18,

Thank you for using Apple Support Communities!

I hear that you're wanting to know more information about deleting photos in iCloud and what happens on all devices when doing so. I'd be happy to help out.

When you use iCloud Photos and delete a photo or video on one device, it's also deleted on all other devices where you're signed in with the same Apple ID. You can learn more about that here:

Manage your iCloud storage - Apple Support

Cheers!

When you turn on photo box and set up iCloud photo library in an iPhone by signing in with your Apple ID and password https://support.apple.com/en-us/HT204264

And if you delete photos from an iPhone https://support.apple.com/en-in/HT205856

The same photos will be deleted from iCloud.com ( even you don't download the originals photos from laptop ) or uncheck the box of photos box in Mac system preferences > iCloud .

As the photo application is in between medium , just to sync photos from device to the iCloud .

It's like a two way mirror delete photos from iCloud - the photos will be deleted from iPhone , or delete photos from iPhone the photos will be deleted in iCloud.com .

In the same way if Mac is synced with iCloud.com , by signing in with same Apple ID and password on the same network , you delete photos from Mac the effect will be seen everywhere .