Yes, wifi is available free of charge throughout the establishment.
Yes, the hotel has free private parking.
Le Relais Guillaume de Normandy
10 km from the Noyelles-sur-Mer station (then the Somme Bay steam railway to reach Saint-Valéry-sur-Somme).
26 km from Tréport-Mers-les-Bains station
A16 towards D40 at Grand-Laviers. Leave A28 / E402 exit Tréport / Rouen / Le Havre / Saint-Valéry-sur-Somme / Le Crotoy.