Request for Downloading River Discharge and Water Level Data

I am requesting river discharge (flow rate in m³/s) and water level (height in meters) in Spain.

I am a student assistant at the Institute of Geodesy (GIS), University of Stuttgart, Germany. Our institute is interested in using river discharge and water level data from all hydrometric stations in Spain for research purposes. We consider your dataset a valuable resource for our ongoing work.

I would greatly appreciate it if you could guide us on how to automatically download data for all stations from your website.
Thank you in advance for your support. We look forward to your guidance.