Cloud Native Computing Foundation - organization that promotes cloud-native technologies and open source projects. Like a governing body that sets standards for modern cloud applications.
Kubernetes, Prometheus, and many other popular cloud tools are CNCF projects with community governance.
CNCF (Cloud Native Computing Foundation) is a vendor-neutral open source foundation, not a cloud provider service. All major clouds support running CNCF projects (like Kubernetes, Prometheus, and Envoy) via managed services or self-managed deployments, but there is no direct 1:1 provider equivalent.