Apple - iCloud Photos is not available as a destination

iCloud Photos is a synchronization service. You didn't say what device your are using or what OS, so it's tough to be specific. But, for example, all the pictures in the Photos Library on a Mac are copied to iCloud Photos Library, And just like that, all the pictures in the Photos Library on an iPhone are also copied to iCloud Photos Library. And all the pictures that arrive at the Photos Library at iCloud are copied back to the other devices.

So iCloud Photos keeps all the pictures on all the connected devices exactly the same. For devices connected to iCloud, iCloud Photos is not a destination that is any different from Mac Photos or iPhone Photos, etc.

Ahh-- you're talking about Google. What did Google say was the problem?