I want to buy iCloud storage annually and not monthly

I'm afraid this option is not available. You could buy 'iTunes and App Store' gift Cards to the required value and redeem them in your account - they are drawn on before your registered payment method: but any music, movie or app purchases will also be drawn from the gift card so you would have to take that into account.

You can also add funds to your Apple ID using your normal payment method, though the same caveat applies - it will also be used to pay for music, movies or apps. Please see Add money to your Apple ID balance - Apple Support