Ah IFR so simple - point and shoot over hundreds of nm's.
VFR, this would normally be a low level route. e.g. from Calais 1500ft contact Lille Info, then Koksijde having first checked notam for low level heli mil activity, usually offshore. Ostend approach 120.6 along coast to COA. Dutch Mil 132.35 (if available due personnel - see standing notam). Passing HSD switch to Ams info 124.3
Coast route - Dutch do not have Right Hand Rule. Note passing Hague the prohibited airspace EHP25. Pass Ijmiuden, 1200ft to remain below Schiphol TMA.
Call De Kooy 120.130 for crossing either Zulu to Oscar or coast route. Then call friendly Texel, to receive VRP for join at 1500ft. Watch for para activities.
More time planning than flying the detail. Have a good flight.