Look for accommodation sooner rather than later. It's in really short supply and I have heard stories of international students being unable to study because they simply cannot access accommodation. Also be careful for scams on the internet, try to visit the accommodation in person if you can, if not, be super careful about following the legal steps as much as possible (this is if you use facebook groups or other informal sites to find accommodation). Make sure you have family/trusted people around when you first move into your city because you will need help if something goes wrong (and also for moral support). Also, some types of student accommodation requires that you furnish the place yourself (including putting in flooring) so you may need people around to help you sort it all out. Other types of accommodation aren't like this but it's worth keeping in mind. Could be worth taking a trip to IKEA before you leave for the Netherlands so you can order all the stuff you need to your new flat in the Netherlands from IKEA when you first move in.
Be prepared to have to spend quite a long time sorting out the registration process in whichever municipality you live in. At the beginning of the academic year, the municipality buildings get swarmed with international students trying to register, consider doing this earlier so you don't have to wait in line.
For healthcare, it depends on your circumstances. If you are an EU citizen (or British, but you should check the validity/type of your card first) you can use your European Health Insurance Card at medical facilities in the Netherlands. Although, you will need Dutch health insurance to work, and if you intend to stay in the Netherlands long term, you will be required to take out Dutch health insurance. Dutch health insurance costs get reimbursed by the Dutch government for people under a certain level of income (although I'm not sure to what extent this is covered for international students). You would need to check depending on the type of visa/residency/EU etc situation to figure this out.
Also, sort out your bank account! Many Dutch supermarkets etc don't take Mastercard or Visa cards because those operators charge the shop extra for transaction fees. So, many Dutch banks have cards with VPay (which is a variant of Visa) or similar. They also have different card systems, e.g. an IBAN number, which British cards don't usually have. So buying things online becomes a hassle (no food deliveries!). My suggestion is to get a card from companies like (Transfer)Wise or Revolut in the short run (some of these are helpful for international travel anyway), and then get a card with ING, ABN AMRO, Rabobank etc once your administrative stuff like registration is all sorted out.
Also get a bicycle! Local student organisations might have bikes on sale for a cheaper cost. Otherwise, lots of international students use Swapfiets (these bikes can be identified by the blue wheel on the front) which is a subscription type service. this is a useful but more expensive option. Generally, bikes are super useful for going out in the evenings, and also for getting to places faster. Not the end of the world not having one, but it's definitely convenient. Buy a good lock for the bike to prevent thefts. Also second-hand bikes that look a little beaten up are less likely to be stolen. I'm told that bike theft is common, although it hasn't happened to me so far.
Good luck with studying in the Netherlands!