Students can vote on these delegates. Finally, each faculty has it's own students organisation. This improves communication and joined vision at a national level. In your letter you have to write down as clear and concrete as possible what you want to do. If there is a positive decision you will get more information.
Free movers have to pay everything themselves.
The rule is that students residing in the Netherlands with a residence permit for studying do not qualify for any form of regular study grant from the Dutch authorities or Universities. The University can only help you to find a room. The language is the next problem. Most of the studybooks are in English but the courses are Dutch spoken. Maybe in future there will be a possibility to follow some courses in English, but this has not been realised yet.