The Zandvoort train station is a five-minute walk from Hotel Paradis. Every half hour a train leaves for Amsterdam from track 2. It also stops in Haarlem. The current timetable of the Dutch Railways can be found here.
Between Zandvoort aan Zee and Haarlem, bus 81 runs via Bloemendaal. This bus will take you to Haarlem city centre. Check here the current timetable for bus line 81. In addition, bus line 80 runs from Zandvoort via Heemstede/Aerdenhout Station and Haarlem to Amsterdam.