Why did my iphone delete the pictures when I removed google

It is not possible to pay for extra storage on your phone; your phone will never have more storage than it did when you bought it.

You can pay for iCloud storage, which used for syncing and backing up (these are 2 unrelated features that both have iCloud in their name, but are not the same).

iCloud is a syncing service, not an archiving service. So anything you delete from iCloud will be deleted from your phone, and vice versa.

But you also mention Google; Google storage has nothing to do with iCloud or your phone. If you have the Google Photos app it syncs photos to Google Photos. This is totally unrelated to iCloud. The way Google has chosen to implement Google Photos is a one-way sync. That is, any photos on your phone are uploaded to Google Photos. If you delete a photo from your phone, it will remain in Google Photos. HOWEVER, if you delete a photo from Google Photos it will be deleted from your phone and any other devices “connected” to Google Photos.

You probably set Google Photos to manage your pictures, once you remove it from your phone you'll no longer have access to those files. You must transfer them from Google to iCloud.

Maybe this can help you with the process https://9to5mac.com/2021/05/31/export-google-photos-to-icloud-photos/

If you delete the Google Photos app it won’t affect the photos on your phone.