3. Create CRD yaml file

apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  name: foos.example.com
spec:
  group: example.com
  names:
    kind: Foo
    listKind: FooList
    plural: foos
    singular: foo
  scope: Namespaced
  versions:
    - name: v1alpha1
      served: true
      storage: true
      schema:
        openAPIV3Schema:
          type: object
          properties:
            apiVersion:
              type: string
            kind:
              type: string
            metadata:
              type: object
            spec:
              type: object
              properties:
                deploymentName:
                  type: string
                replicas:
                  type: integer
                  minimum: 1
                  maximum: 10
            status:
              type: object
              properties:
                availableReplicas:
                  type: integer