Re: I am getting alert on my I phone 6+: I could storage finished.
Welcome to iMore!
Is it the internal storage on your phone that is out of space, or is it iCloud?
You cannot add more storage to your iPhone. If it's on your phone, you'll need to delete some things. Go to Settings -> General -> Storage & iCloud -> Manage Storage
You should see your apps and what is using up space in order to delete. You may have a lot of iMessages that can be deleted (there's a setting in Settings -> Messages where you can set a time limit). Other apps may take a lot of space with cache that deleting the app should clear. You can then reinstall it.
If it's iCloud that is full, you can get additional storage. More info is here:
https://support.apple.com/en-us/HT201238
Good luck!