If we uninstalled google drive from our iphone, will it also delete the data in the cloud?It should not. Your google drive (and the contents in it) are hosted by Google's servers (the cloud). Your iPhone is using Google Drive as an extension of accessing your Google Drive.
Go to Settings > Photos & Camera
What settings do you have toggled on? To keep storage off of my iPhone, I pay $0.99 a month for 50GB of iCloud storage space. I have 'iCloud Photo Library' toggled on, Optimize iPhone Storage and iCloud Photo Sharing toggled on. When I take a picture on my iPhone the picture is uploaded to iCloud and the storage on my iPhone is not used so I have ample storage space on my iPhone at all times. I also have the ability to organize my photos, create albums, all in the iCloud from my macbook, iPhone or iPad.
Let me know if you have any questions.