The connectivity between iPhone and iCloud means that if you delete a picture on your iPhone, it's also removed from iCloud.
The answer is NO! Neither iCloud Photos will delete the pictures once you turn them off, nor you lose access to images captured on your device. The local copy of every image or screenshot captured on the device will remain on the phone. However, you will lose access to the images captured on other devices.
Delete photos in iCloud Photos. iCloud Photos uses your iCloud storage to keep all of your photos and videos up to date across your devices. You can make more space in iCloud when you delete photos and videos that you no longer need from the Photos app on any of your devices.
Click iCloud Manager > Log in iCloud with Apple ID and password. After photos imported to iCloud, the photos will appear in your iDevice, but they will not consume the storage of your iPhone. All the photos stored on iCloud will consume your iCloud storage.
The biggest culprits are likely to be Photos, so start with that, and make sure the 'Optimize iPhone Storage' option is enabled. Because you cannot add storage to your phone. It will always have the amount it came with. You have bought space in Apple's synching service, iCloud.
Videos, photos and large email attachments are large files that fill up storage space quickly. Apps like Mail, Contacts, Calendar, Reminders and Notes automatically access the cloud and store additional data there.
Photos stored in iClouds photo stream are only stored for up to 30 days and up to 1000 photos (whichever you reach first). You should save any photos you want to keep to your photo roll or iPhoto within the 30 days allocated.
When you turn on iCloud Photos, your photos and videos automatically upload to iCloud. They're not duplicated in your iCloud backup, so you should keep backup copies of your library. Use the steps below to download copies of your photos and videos to your Mac or PC. Or you can import your library to your Mac or PC.
When you turn on iCloud for an app, its information is safely stored in iCloud and automatically kept in sync across your devices. When you turn it off, the app no longer connects with iCloud, so your data exists only on your device.
Device storage is the available storage on your iPhone, iPad, Mac or other Apple device. iCloud storage keeps your photos, files, notes and more up to date and available across all of your devices.
On iCloud.com, you can see how much iCloud storage you have and how much is available. in the toolbar, then click Your iCloud Storage. Below the storage bar, you see a list of apps and features and how much iCloud storage they use. The apps and features that use the most storage are at the top of the list.
Delete files permanently from Creative Cloud
Select the files or folders that you want to permanently remove from the cloud, and then select Permanently delete. Note: Press Shift + Right Arrow key (→) to select multiple files or folders to delete. Right-click view of the image showing the Delete permanently option.
Remove videos, books, and music stored on your phone
Sometimes what's taking up the most amount of storage are the data and documents stored within an app on your phone. You can find out if that's the case by once again heading to Settings > General > iPhone Storage and then clicking on an app.
You will no longer be able to download apps or save new photos, videos, or other files. Your iCloud Photo Library will struggle to sync with your iPhone. You may notice a drop in your iPhone's performance. You will get quite a few error messages and warnings.
That's pretty significant. To optimize your photos and videos, go to Settings > Photos and toggle on Optimize iPhone Storage (for this to work, you'll need to have the iCloud Photos setting above it enabled).
Device storage is the available storage on your iPhone, iPad, Mac, or other Apple device. iCloud storage keeps your photos, files, notes, and more, up-to-date and available across all your devices.
It may be that your iPhone has accumulated cache files over a period of time, and these caches are now too large for your iPhone to handle. In this case, what you can do is to clear the cache files on the iPhone to free up memory space.
When you charge iPhone it will automatically be backed up to iCloud Over your wifi. A simple and sure test is to log on to iCloud.com (via a browser) using the account that is suppose to have the photos. You can select the Photos icon once logged in, and easily view which photos are already in iCloud.
How to access iCloud Photos. Open the Photos app. Select Library to see your photos.
Turn off iCloud Photos in iCloud and all of your devices
Photos and videos stored in iCloud will be deleted 30 days after you stop using the service.