I’m pretty new to Cloudflare so I don’t know what “Root Domain” is.
The only thing I’m doing is
Clicking on the “Add Site” button,
Typing my domain(purple.nah),
And just got the:
“We were unable to identify <mydomain.domain> as a registered domain. Please ensure you are providing the root domain and not any subdomains, etc, etc”
To add a domain to Cloudflare, it would need to be a valid ICANN TLD. You can purchase a new domain via Registrar a cost-price: Register a new domain · Cloudflare Registrar docs or you can use a domain from any other Registrar too, but it has to be an ICANN TLD.