Yes, as long as you are betting with one of the online licensed bookmakers recognised by the Netherlands Gaming Control Board, then it’s perfectly legal.
Is Online Sports Betting Legal in the Netherlands? At the time of writing, there are now 24 operators who hold Dutch licences, and are safe to bet with. The most important takeaway from the whole document is that, on 1st October 2021, new licences became available for both international and Dutch betting sites. The Remote Gambling Act (KOA) came into force on 1st April 2021 and brought about big changes for the better, as far as gamblers are concerned. Bonuses are only eligible for players 24+.