how do i make i cloud storage payment

Hi gokul180,

Welcome to Apple Support Communities, we're glad to assist. We understand that you need to know how to pay for your iCloud storage. You'll want to make sure to have a payment method on file. We see that you came to us from the article Change, add, or remove Apple ID payment methods, that's definitely the one to use to add your payment method. Once you have your payment method on file, your card will be charged for whichever iCloud storage plan you choose. You'll be billed mostly, and you will receive an email reminding you of the upcoming payment. Read more about that here: Upgrade to iCloud+.

Hope this helps.