i don’t know how to buy storage, is it my phone ?

If you're referring to an iPhone's internal storage, you can't.

If you're referring to storage on Apple's servers, click on 'get more iCloud storage' in the Related Article above.

If you're referring to something else, say what it is.

(221410)

yamileth247 Said:

"i don’t know how to buy storage, is it my phone ?"

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Seems you need to clear some space.

Troubleshooting iPhone Storage:

Internal storage cannot be upgraded. It is what it is. So, the maximum internal storage capacity never increases, even if you upgraded your iCloud plan. Learn More here: What's the Difference Between Device Storage and iCloud Storage? Apple Support. 

So, what to do:

Clear Space:

Try clearing internal storage though use of the following:

What Space to Clear:

A. Clear Temporary Internet Files:

Clear your Temporary Internet Files(Cookies & Cache) of Safari:

• Cookies perform remembrance of certain site-entered data.
• Cache keeps a snapshot of the last time you visited a site.
• Go Here: Clear the History and Cookies from Safari on your iPhone, iPad, or iPod Touch - Apple Support

And...



B. Clean TV and Music Libraries:

Remove all unneeded files from your TV and Music Libraries. Full-Movies take up 2-4GB typically, and a bunch of those would take up a load of storage, ideally. So, if you have any movies that are not needed, then delete them.

And...

C. "Other" being the Culprit:

System Data (formerly called "Other"), basically contains unnecessary files such as caches that are used for system ease of use - all of which gather over time. Caches would be being used for remembrance of application use.  Use my User Tip: How to Clear "Other" in your iPhone's Storage - Use Backup - User Tip.