iCloud Photo Library and iCloud Drive Question

I have read that by using iCloud Photo Library, if I deleted photos on my phone, it will be deleted on the iCloud. Is there any solutions to avoid that?

The iCloud Photo Library is a syncing service, so yes, deletions made on your phone are synced to iCloud. Avoid this by not using the iCloud Photo Library. This is the design of iCloud Photo Library.

Another question is can I move all my photo from iCloud Photo Library to iCloud drive and using the drive to store my photos?

Yes, but you won't save space by doing this, and the photos will be not be visible on your phone in the camera roll. Only in the files app. If you access them in the feels app, they will be copied to the camera roll.

I’m very confused as Apple have no instructions using these stuff

I disagree.

See >> https://support.apple.com/en-ca/HT204264 or https://support.apple.com/en-ca/HT204570