When we create a Pod in Kubernetes, we can set the environment variables for the container(s) the Pod will create. We can do this by the env key. env is an array of the name and value of environment variables.

apiVersion: v1
kind: Pod
metadata:
  name: name-of-pod
spec:
  containers:
    - name: container-name
      image: image-name
      env:
        - name: NAME_OF_ENVIRONMENT_VARIABLE
          value: 'Value of environment variable

References

• https://kubernetes.io/docs/tasks/inject-data-application/define-environment-variable-container/