Because my iPhone is full storage

Here are some helpful articles that can guide you on how to free up storage space on your phone.

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

How to check the storage on your iPhone and iPad - Apple Support

Manage your photo and video storage - Apple Support

Manage your photo and video storage - Apple Support

Clear Other storage on your iPhone or iPad - Apple Support

Clear Other storage on your iPhone or iPad - Apple Support

Hi.

You are referring to your iPhone storage and not the iCloud storage for backup?