Here at the germany authority BSH (Bundesamt für Seeschifffahrt und Hydrographie) you will find all the stations for which one can obtain tide Tables for the german north-sea-coast:
https://www.bsh.de/DE/DATEN/Gezeiten/gezeiten_node.html

The level of the water depends not only on the tides but also on the wind. So here also at BSH you can look for a prognosis of the water level with the parameters of tide and Wind. And this prognosis is for 24 hours, for 0-3 days and for 3-6 days. In this example for Schulau on the river Elbe, where a huge marina is located.