How do I buy more storage for my iPhone

You can't, the storage on an iPhone is a fixed size.

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

https://support.apple.com/en-us/HT201656

Manage your photo and video storage

https://support.apple.com/en-us/HT205703

Clear Other storage on your iPhone or iPad

https://support.apple.com/en-us/HT211686

I need more storage. You guys acmed me into buying more iCloud space 200 g or MG or whatever

ans my iPhone is at 64g out of 65g

it’s grey - I deleted tons of stuff and it’s not moving. Call me. I’m a customer 20 years 973-524_4118 Tony