iCloud and Apple ID though use the same credentials but they are different.
Apple ID :- An Apple ID is the account you use to access Apple services like iCloud, the App Store, the iTunes Store, Apple Music, and more. It includes the email address and password that you use to sign in, and all the contact, payment, and security details that you'll use across Apple services.
No matter where you create your Apple ID, just remember to use the same one to sign in to every Apple service. That way, you can access and manage everything with a single account and password.
iCloud :- iCloud is built into every Apple device. That means all your stuff — photos, files, notes, and more — is safe, up to date, and available wherever you are. And it works automatically, so all you have to do is keep doing what you love. Everyone gets 5GB of free iCloud storage to start, and it’s easy to add more at any time.