Why do I have 200 GB of cloud and my phone is using its 50GB but it’s saying My storage is full. My phone itself has 50GB ORiginally

They are two separate and different things: your phone storage is the storage on your device itself. Then there is iCloud Storage associated with your Apple ID.

Depending on what settings you have made on your iCloud, various data (photos/notes/bookmarks/backups/app data, etc.) which is saved on your iPhone is also uploaded as a copy on iCloud. But the data on your phone continues to stay on your phone and takes up storage space.

So, the message you are seeing, is most probably because you are running out of device/iPhone storage space. Here are some recommendations on how to manage storage space on your iPhone: How to check the storage on your iPhone, iPad, and iPod touch - Apple Support

More importantly, read Manage your photo and video storage - Apple Support to optimize iPhone storage space when saving in Photos app.

Remember what photos you choose to delete on your iPhone will also be deleted on iCloud. So only delete unwanted photos!

iCloud is for sharing information amoung devices and for backing up your device. Having iCloud storage doesn't expand what storage you have on your device.

https://www.cnbc.com/2019/04/05/how-to-save-space-on-my-cluttered-iphone.html

Be sure to do a backup before deleting things.

Remember iCloud and other services are syncing serives. Delete a photo in one place deletes the photo in every place. I like to back my devices to a computer.

R