WHOIS and RDAP
WHOIS is the old text protocol for domain registration data; RDAP is its modern, structured replacement, and the one registries now maintain. This lookup uses RDAP through rdap.org, which routes each query to the right registry.
Personal contact details are usually redacted for privacy, so you will see the registrar and dates rather than the owner's name.
Questions
Why is the owner hidden?
Privacy rules and redaction services hide personal data in most public records.
Why is there no data for my domain ending?
A few country registries do not publish RDAP yet.
What does clientTransferProhibited mean?
A lock that stops the domain being transferred without your action. It is normal and protective.
How do I find who owns a domain?
Contact the registrar shown, or use the contact form some registrars provide for privacy-protected domains.