Unable to create iCloud account on my MacBook

Re: "Problem creating icloud account : I am trying to create an account for my MacBook"

Seems, if logged in to your Mac with your correct Apple Account details:

you would already have the 5Gb free iCloud account on your Mac.

If you do not already have an Apple account: How to create a new Apple Account - Apple Support

Click the Black Apple icon on the left in the top menu-bar of the Mac.

Choose "System Settings" from the menu that opens.

Click [Your name] at the top in the left sidebar of the window that opens

On the right Click the > beside iCloud.

There, you can customize the settings ...turn options on or off .... click "Show all" to see all the options.

(If you want more storage than the free 5 Gb storage ...

you can upgrade from there, and pay using your Apple account.

More info: Manage iCloud storage on Mac - Apple Support

NB: Seems iCloud is mainly for sync of data across devices.

(Eg: If you delete an item anywhere it deletes everywhere that item is in sync)

Some of us use external storage devices instead.)

Apple Support suggests we: Archive or make copies of the information you store in iCloud - Apple Support