Hi @Aminsn, 

Having Unity Catalog enabled is a requirement for vector search. Source: Vector Search - Requirements. If you're referencing this tutorial Creating High Quality RAG Applications with Databricks I think that many of the required features also rely on UC and there's not much you can do to avoid that. I'm not aware of a non-UC tutorial for the scenario you described.

These are the docs on how to enable a workspace for UC, in case you'd like to proceed in this way: https://docs.databricks.com/en/data-governance/unity-catalog/enable-workspaces.html