my iPhone wouldn't open and function

How to check the storage on your iPhone, iPad, and iPod touch

https://support.apple.com/HT201656

- General article on seeing what is taking up storage on an Apple mobile device and tips on how to clear some storage space.

How to Free up space on your iPhone [Apple YouTube video] --> https://www.youtube.com/watch?v=bnhuHSv_WrI

Note there's different kinds of "storage". Click on this link to "Learn the difference between your device and iCloud storage, ways to manage your space" and upgrading to iCloud+ if you need more --> https://support.apple.com/HT206504

If you can't back up to iCloud, click here --> https://support.apple.com/HT203516

If restore from iCloud backup failed, click here --> https://support.apple.com/HT212201

Manage your photo and video storage --> https://support.apple.com/HT205703

Hi,

Sorry to hear you are having issues with your device storage.

I would first recommend to update your iOS to 15.2, especially if you are running iOS 14.

That being said, I assume you also don't have enough storage available to update your device. The following resources explain how to manage device storage:

• How to check the storage on your iPhone, iPad, and iPod touch
• How iOS and macOS report storage capacity - Apple Support
• If you need more space for an update on your iPhone, iPad, or iPod touch

Ultimately, if the storage is almost full, and you have backed up your content and data, i would go to Settings > General > Reset > Erase all Content and Settings.

Once the device restarts with the iOS Setup Assistant, do not restore from an iCloud backup.

First, try to update your iPhone in Settings > General > Software Update.

Once the update completes, sign into your iCloud Settings as normal. Content from iCloud will manually transfer to the device once you sign in.

Hope this helps.