Furthermore, if you mistakenly mistyped exampl instead of example or even selected wrong TLD like .co instead of .com, unfortunately this is treated “as-is”, therefrom if you’ve didn’t double-checked and continued the process of domain registration, not just with Cloudflare Registrar, rather with any other is the same, you’d have to register a new correct domain again.
There is no possibillity to “change”, “replace” or “swap” wrong domain name with correct one at neither domain registrar.
You should register a new domain, hopefully if it’s still available.
Otherwise, may I ask if you’ve selected wrong zone (domain) and purchased Pro plan for it, therefrom want to cancel/refund and subscribe and pay for the correct one?
If so, kindly the correct was is to create a Billing Ticket here https://dash.cloudflare.com/?to=/:account/support by selecting Billing, therefore share your ticket number with us so we could escalate your case to he team. Thank you in advance.