@Sulfikkar Basheer Shylaja​ Is your cluster using a custom docker image? The problem here is, the local filesystem path (file:/) is only supported if you use a custom docker image. In regular DBR runtimes, the init script can only be pulled from dbfs, s3, gcs or adls.

You might have to adapt to storing the init script in one of the above locations because the cluster cannot read the file from your local filesystem.

This is not possible even through UI.

There are different ways to upload a file to DBFS that you can explore-

dbutils, API, CLI