Q: How to Buy more iCloud Space

I am pretty sure you can use store credit. But you get 5 gigs, do you really need more?

Yep you do. Go to Settings>iCloud>Storage and backup>Buy more storage. Sorry if you already know this.Cheers.

I need to buy more space for I phone, how can I buy it online?

dcherenfant wrote:

I need to buy more space for I phone, how can I buy it online?

This Apple Help page explains how to buy more iCloud storage:

iCloud storage upgrades and downgrades - Apple Support

Note that this storage is paid for monthly, not one-off.

From the way you've phrased your question, it's possible you are under the impression this will increase the storage actually on your phone: it won't. The storage is online, on the iCloud server. It's not possible to increase the internal storage of any iPhone model.

You can buy iCloud storage directly on your iPhone.

iCloud storage upgrades and downgrades - Apple Support

You cannot modify your iPhone's physical storage however.