When you visit basa.nl, basa does not collect your data.
The hosting provider of this domain logs every visit to every URL, including your IP address and 'User Agent', and makes those logs available to basa.
When you contact basa via https://basa.nl/contact/, the Dutch AVG regulations apply. Your e-mail messages are possibly stored forever. The purpose of storing your messages is to (re)read them and to be able to reply to them. Your messages are not published. If you want, you can request the messages basa has stored from you (based on your e-mail address). If you want, you can ask basa to remove your messages.
The data you produce are not shared with third parties.