help !

hi apple

very soon i will buy the iphone x

my question is about the icloud

i have to upgrade my icloud space from 5 gb to 50 because i wanna backup all my stuff

to the new iphone, and 5 gb its not enough.

so i wanna know if can i pay for 50gb space in icloude only for a one month and not for every month.

one time payment. just to backup my stuff to the new iphone and not backup and payment for every month.

thx alot and sorry for the bad english.