Apple removed "App store" option from new iTunes software. so you will need iPhone or iPad.

If you already have iTunes account logged in on your iPhone/iPad, then first you need to sign out by going to Setting-> Apple ID->scroll down and click Sign out or you it will not give you option to register new account in App Store.

    • Open App Store on your iPhone/iPad
    • Choose any "FREE" app and Click on "GET" button.

    • Then choose "Create New Apple ID"

    • Then choose "Use Email Address"
    • Fill Email and Password
    • Select Country "United States"
    • Agree to Terms and Conditions.
    • Click "Next" button

    • Fill your Personal Information
    • Again click "Next" button

    • Choose Payment Method "None"
    • Fill "Billing Address" (To avoid extra charges as tax choose state - Alaska, Delaware, Montana, New Hampshire or Oregon)
    • Then click "Next" button

    • Verify your phone number and Email by entering OTP, you can use number from your own country.

    • Last step enter your iPhone/iPad passcode and click continue on welcome screen.

You are done.