@javierguibert
That seems difficult.
Tides are calculated by Windy by using the harmonic calculation method:
https://community.windy.com/topic/4841/tide-forecast-on-windy
For this calculation it is necessary to get reference measurements for each harbour or location where tides forecast is provided:
https://tidesandcurrents.noaa.gov/about_harmonic_constituents.html
These measurements are generally made by tide gauges.
Windy has tried to collect more data around the world, but apparently did not succeed.

Indeed, there are many countries where these data are not available in open source. In these countries their national hydrographic institute provides the tide forecast.

Could we use satellite observations to measure sea level changes? This is already possible, but probably is lacking of precision in some places. The tidal heights depend heavily on the shape of the coastline and the satellite measurement resolution does not provide sufficiently detailed data.