Ensure you have enough cash (in euros) to cover your expenses for the first couple of days in the Netherlands
After acceptance to the exchange programme/courses, you'll be requested to upload a picture for your student ID
After receiving your university login keys (ERNA details), log on to the university systems by using the direct link mentioned in the email about this matter
Make sure your passport is valid for the time that you'll be staying in the Netherlands and check with the authorities in your home country how many months your passport still needs to be valid for when you return there
Prepare the necessary documents for your visa and/or residence permit (if applicable), and if you need a visa, obtain it before you travel