@Hemant Kumar​  I found out that mounting an S3 bucket is possible if using the Web UI within a Notebook.

https://towardsdatascience.com/how-i-connect-an-s3-bucket-to-a-databricks-notebook-to-do-analytics-a...

@Kaniz Fatma​  yes, I would still need help on this one.

Would it be a viable solution to use a global init script from dbfs for the cluster created via Databricks Clusters API ?

https://docs.databricks.com/clusters/init-scripts.html#cluster-scoped-init-script-locations