How to access contacts app on iPhone cloud

On an iPhone, iCloud is designed to be viewed by using the apps on the device (e.g., the Contacts or Phone app for Contacts, the Files app for iCloud Drive, the Photos app for iCloud Photos, the Notes app for notes, etc.).

You can use an internet browser and log into icloud.com but what you can access via a browser varies by device. See: Which iCloud.com features are available in the browser on your device - Apple Support

Set up and use iCloud Contacts - Apple Support Read this first!

Hope that helps! If not, please send a photo/screenshot of what you're looking at on your screen and I'll guide you from there!