If you are not familiar with the oc command, refer to OpenShift - Getting Started with the oc command.

I like to think of a machine as OpenShift representation of a Virtual Machine, such as an Amazon Web Services (AWS) EC2 Instance, or a VMWare Virtual Machine, and then a Node, and then the pods running on the node. Machine Configs can be used to configure the Virtual Machine Operating System, such as configuring a Linux systemd service such as sshd or chronyd or Network Manager.

A Machine Set is used to create machines with certain default configurations, such as 4 CPUs. 

The oc get machinesets command can be used to display the desired, current, ready and available count for a certain type of machine, in the openshift-machine-api namespace.

~]$ oc get machinesets --namespace openshift-machine-api
NAME                DESIRED   CURRENT   READY   AVAILABLE   AGE
my-cluster-edge     2         2         2       2           140d
my-cluster-infra    3         3         3       3           140d
my-cluster-worker   2         2         2       2           143d

The output option can be used to output the YAML for each machine set.

oc get machineset/my-cluster-worker --namespace openshift-machine-api --output yaml

Which should return YAML that looks something like this. Notice in this example that there are 2 replicas, thus this machine set will ensure there are always 2 machines.

apiVersion: machine.openshift.io/v1beta1
kind: MachineSet
metadata:
  creationTimestamp: "2021-07-16T17:10:51Z"
  generation: 4
  labels:
    machine.openshift.io/cluster-api-cluster: my-cluster
  name: my-cluster-worker
  namespace: openshift-machine-api
  resourceVersion: "485196036"
  uid: 57d19e1d-6533-4a76-ad21-f5109e18f357
spec:
  replicas: 2
  selector:
    matchLabels:
      machine.openshift.io/cluster-api-cluster: my-cluster
      machine.openshift.io/cluster-api-machineset: my-cluster-worker
  template:
    metadata:
      labels:
        machine.openshift.io/cluster-api-cluster: my-cluster
        machine.openshift.io/cluster-api-machine-role: worker
        machine.openshift.io/cluster-api-machine-type: worker
        machine.openshift.io/cluster-api-machineset: my-cluster-worker
    spec:
      lifecycleHooks: {}
      metadata:
        labels:
          node-role.kubernetes.io/compute: ""
          node-type: general
      providerSpec:
        value:
          apiVersion: vsphereprovider.openshift.io/v1beta1
          credentialsSecret:
            name: my-secret
          diskGiB: 120
          kind: VSphereMachineProviderSpec
          memoryMiB: 65536
          metadata: {}
          network:
            devices:
            - networkName: my-network
          numCPUs: 4
          numCoresPerSocket: 1
          snapshot: ""
          template: my-cluster-rhcos
          userDataSecret:
            name: worker-user-data
          workspace:
            datacenter: my-datacenter
            datastore: my-datastore
            folder: /foo/bar
            resourcePool: /foo/barb/Resources
            server: server1.example.com