Number servers required for Tanzu?

[JonathanGer]

How many nodes/servers are required to install Tanzu?

1. Tanzu Application Service I see here TAS for VMs on vSphere Requirements |    VMware Tanzu Docs
2. PKS is here vSphere Prerequisites and Resource Requirements |    VMware Tanzu Docs
3. vSphere 7 requires vCloud Foundation VMware Cloud Foundation 4.0 Release Notes

Confusing....