Transferring iCloud storage from iPhone 8 to the 12

Hello! I recently just decided to upgrade my phone to the iPhone 12 since I have had the 8 for awhile and I didn't have enough storage to do a backup on my phone even after saving my photos to another platform and getting rid of any necessary files, I only had about 38.8 MB out of the 5 GB when looking at my phone and even after looking at YouTube videos and checking different ways I still couldn't backup so I bought some storage in order to do the backup. My question is once I transfer all my info to the 12 from the 8 would I be able to cancel it since it's already in the new phone? Thank you!