How do I delete Photos from My iPhone But Keep Them in iCloud?

I want to keep my old photos only in iCloud.

I found a possible answer.

• Go to your iPhone settings.
• Tap on your Apple ID or name.
• Navigate the ‘iCloud’ option and tap on it.
• You will see a green toggle or ‘On’ button next to your iCloud Photos. Click on it and turn off iPhotos.
• Below iCloud, you will have the “My Photo Stream” option. Click on it and turn it off also.
• It will delete the iCloud album from the iPhone but keep it in the iCloud.

My question is: Will this method work?