I am unable to find the Flow Builder option in the Admin Center.
The account either has Zendesk Suite, or Support and Chat with the Agent Workspace enabled. I have also read this article to understand recommendations and limitations: About Zendesk messaging.
- Verify that Agent Workspace is enabled in your account.
Click Zendesk Products () > Admin Center > Channels > Messaging and Social.
- Select Messaging setup.
- Select Enable messaging for your account.
Now that messaging is enabled, you will see the Flow builder option under Bots and Automation > Bots.
For more information, see this article: About Flow Builder.