<p>Whenever the deployment has been created needs to trigger a custom function or webhook. Does Kubernetes provide any option to do this?</p>

az rnd
<p>Custom Resources are an extension to the Kubernetes API. Just having them standalone is not going to do anything functionally for you. If you need to perform a specific action upon change or deployment or bare existence of a given custom resource, you will need a custom controller that does that.</p>
<p>One of the possible implementations is an Operator. I specifically mention that, as it is fairly easy to create the controller alongside the custom resource definition using <a href="https://sdk.operatorframework.io/" rel="nofollow noreferrer">Operator SDK</a>. However you can <em>just</em> create a custom resource definition and deploy a <a href="https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/#custom-controllers" rel="nofollow noreferrer">custom controller</a>.</p>
<p>On a closing note: there are other ways your question is very broadly formulated so there is a vast variety of ways to answer, and this is just one option.</p>
