If you are not familiar with the oc command, refer to OpenShift - Getting Started with the oc command.
There are different ways to configure a container with environment variables.
A config map contains files, variables, and command line options that can be used by one or more applications, as a way to create separation between applications and the files, variables, and command line options being used by the applications.
Or, a secret can be used, so that the data is encoded (not encrypted).
For example, a config map could contain the variable foo=Hello or a secret could contain foo=V29ybGQ= (which is Hello base 64 encoded), and then one or more pods could use the config map or secret to return Hello from the foo key.
Let's say you create a secret named "mysecret" that contains the key "foo" and value "bar".
oc create secret generic mysecret --from-literal=foo="bar"
The oc get secrets command should show that the secret exists.
~]$ oc get secrets NAME TYPE DATA AGE mysecret Opaque 1 3m11s
The --output yaml or --output json options can be used to display the YAML or JSON details of the secret. Notice that the "foo" key contains "YmFy" instead of "bar". This is normal, because the secret value is base64 encoded.
~]$ oc get secrets mysecret --output yaml apiVersion: v1 data: foo: YmFy kind: Secret metadata: creationTimestamp: "2021-11-18T07:12:09Z" name: mysecret namespace: default resourceVersion: "448072461" uid: 4104a646-84e2-46c3-bd59-408e2f7ee807 type: Opaque
On a Linux system, the base64 command can be used to decode the value.
~]# echo YmFy | base64 --decode bar