It's "Hyvää joulua" or "Hauskaa joulua". Happy New Year is then "Hyvää uuttavuotta".
Gelukkige Onafhankelijkheidsdag is the word for Happy Independence Day. This is translation from English to Dutch.
Vrolijk Halloween
I would say: 'Happy thanksgiving'. Because Thanksgiving is an American holiday, not a Dutch, there is no specific translation for it.
Christmas = Navidad
'Happy birthday' is 'fijne verjaardag' in Dutch.
Heb een fijn leven.
Juullimi Ukiortaassamilu Pilluarit.
Do you mean how do the Dutch say it?? If so it is Gelukkige Bithday.
feliz novo de natal
Nobody is always happy. Dutch children are also not always happy.
In Belgium, you can say "Gelukkig Nieuwjaar" to wish someone a Happy New Year.