Doc https://docs.openshift.com/container-platform/4.16/machine_management/creating-infrastructure-machinesets.html#binding-infra-node-workloads-using-taints-tolerations_creating-infrastructure-machinesets

Tip
kind: Node
apiVersion: v1
metadata:
  name: <node_name>
  labels:
    ...
spec:
  taints:
    - key: node-role.kubernetes.io/infra
      effect: NoSchedule
      value: reserved
  ...

should be updated to below, or report syntax error: error parsing edited-file: error converting YAML to JSON: yaml: line 58: did not find expected key

kind: Node
apiVersion: v1
metadata:
  name: <node_name>
  labels:
    ...
spec:
  taints:
  - effect: NoSchedule
    key: node-role.kubernetes.io/infra
    value: reserved
  ...

Similar
kind: Node
apiVersion: v1
metadata:
  name: <node_name>
  labels:
    ...
spec:
  taints:
    - key: node-role.kubernetes.io/infra
      effect: NoExecute
      value: reserved
  ...

should be updated to 
kind: Node
apiVersion: v1
metadata:
  name: <node_name>
  labels:
    ...
spec:
  taints:
  - key: node-role.kubernetes.io/infra
    effect: NoExecute
    value: reserved
  ...

And doc https://docs.openshift.com/container-platform/4.16/machine_management/creating-infrastructure-machinesets.html#infrastructure-moving-router_creating-infrastructure-machinesets
Below part should be indentation, 
  spec:
    nodePlacement:
      nodeSelector: 
        matchLabels:
          node-role.kubernetes.io/infra: ""
      tolerations:
      - effect: NoSchedule
        key: node-role.kubernetes.io/infra
        value: reserved
      - effect: NoExecute
        key: node-role.kubernetes.io/infra
        value: reserved
should be updated to
spec:
  nodePlacement:
    nodeSelector:
      matchLabels:
        node-role.kubernetes.io/infra: ""
    tolerations:
    - effect: NoSchedule
      key: node-role.kubernetes.io/infra
      value: reserved
    - effect: NoExecute
      key: node-role.kubernetes.io/infra
      value: reserved

Doc https://docs.openshift.com/container-platform/4.16/machine_management/creating-infrastructure-machinesets.html#infrastructure-moving-monitoring_creating-infrastructure-machinesets
1. Change
watch 'oc get pod -n openshift-monitoring -o wide' 
to 
oc get pod -n openshift-monitoring -o wide

now report error
$ watch 'oc get pod -n openshift-monitoring -o wide'                                                             
zsh: command not found: watch