The register
The register lists Mill Hill County High School in London as a licensed sponsor on Skilled Worker, an entry that goes back to at least 2026. Its rating on the register is Worker (A rating).
Mill Hill County High School is the registered name (Companies House number 07713287), a company limited by guarantee on the register since 2011. The registered office is at Mill Hill County High School Worcester Crescent, Mill Hill, London, NW7 4LL, NW7 4LL. By its SIC codes the business is in education.
A licence says an organisation may sponsor; it does not say it is hiring today. The way to find out is the same as for any employer: the careers page, the job boards, and a direct approach with a UK-style CV that says early that sponsorship would be needed.