@Simon G-L​ :

It seems like there may be some confusion with the cluster state and the UI.

When you create a cluster in Databricks, it will be assigned a unique name and ID. If you delete that cluster and create a new one with the same name, it will have a different ID.

To access the Data menu, you need to be connected to a cluster that has access to the data. When you create a new notebook, you will be prompted to select a cluster to attach it to. Make sure to select the new cluster you created.

If you are already in a notebook and need to change the attached cluster, you can do so by selecting "Attach" from the "Clusters" menu in the top-right corner of the notebook interface.