My iPhone storage is full and I purchased extra ICloud storage but my phone will not allow me to back it up. Is there a way to transfer everything from my phone storage to the iCloud storage to clear space on my phone?

iCloud storage can only help in a limited way with a shortage of storage on a device. See the information in the following and note in particular the instructions about Optimize iCloud Photos: What's the difference between device storage and iCloud storage? - Apple Support

fawn1477 Said:

"My iPhone storage is full and I purchased extra ICloud storage but my phone will not allow me to back it up. Is there a way to transfer everything from my phone storage to the iCloud storage to clear space on my phone?: This iOS and system data take alot of my phone space how can I free up them so I can get a little space on my phone"

-------

Getting this Bug Fixed:

Set Up your iPhone Anew:

Use this Site: What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support. If you have no concern for losing data, you could reset this as if you were to sell it. Just know that all content would be erased from your device. Perform as instructed, ending logging out of iCloud, and backing up the device. Once reset, it would start up anew. It would come to the startup screen. Proceed from there with the login. Contact the developers, if you need to reinstall something that requires as key. And keep the Security Software off.

Prior to the Reset:

Enable Items in iCloud:

Once items are enabled on iCloud, then all would be accessible through iCloud. Once you log back in to the same Apple ID and enable these items in iCloud setting on this, the same items will show up.

How to Enable iCloud Items:

Log into iCloud on the phone. Then, tap Contacts in iCloud settings, making it green.

1. Go To: Settings
2. Tap: Your Name (Top-Item)
3. Tap: iCloud
4. Tap: an item (so that it is green)

am using iPhone 6splus and and my phone storage is full how can I free up my phone or is there space and how can I get a more space on my phone

And how come.. system data and iOS got a lot of space how can I free up them so i can get a space on my phone

This iOS and system data take alot of my phone space

how can I free up them

so I can get a little space on my phone

My iphone storage is full