Most of my photos disappeared from iPhone can I retrieve from cloud
How can I recover lost photos
If you used purely iCloud backup then quite possibly.
OR
If you use iCloud Photos then it depends how they were removed.
: If you actively deleted them then no, they're gone.
: If in Settings, Your name, iCloud, Photos is turned off, try turning it back on,
If you have access to an iPad or computer, sign into iCloud.com and look for photos there.