how can I stop my inf going to icloud

Read the documents in these links:

Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac:

"You can sign out of iCloud on one of your devices, or you can sign out on all your devices to stop using iCloud."

https://support.apple.com/HT208242

Change your iCloud feature settings

https://support.apple.com/en-us/HT207689 - "You can also turn off iCloud completely."

The precise way is sign out Apple ID from the device it could be Mac / iPhone / iPad Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac - Apple Support

If you mean information like applications data synced with iCloud turn off the boxes for application see the article Change your iCloud settings - Apple Support

Apple privacy support documents

Apologies the same link is posted by me .