There are 2 currents layers in Windy.
Currents which includes all type of currents. As wind is the main factor of ocean circulation, its effect is taken into account (but not sure for a local wind)
Tidal currents is deducted from variation of sea altimetry
Concerning waves models, WW3 model is said to include the effect of surface currents, WAM model apparently not.
Depending where you usually sail, these layers are interesting but it is advised to rely on other traditional and official information sources for currents and their effect on sea surface, specially near the coast.