GDPR compliancy is only required for EU members but perhaps you're asking on behalf of others
I did research about GDPR and getting the site compliant beforehand and found out that the forum software (vBulletin 4.x) is end of life and is getting no more updates or additions (apart from security patches) so it can't be done through a software update, it would need to be custom coded. We do of course collect information, otherwise the forum would be impossible to run.
One solution would be to add a custom field when registering an account and if you do not agree with the collection of data (such as storage of username, e-mail address, ip address etc) you cannot register because those are needed for the forum to function. If you no longer agree, contact us and all your information (account) and posts will be deleted. We do not store any information for any other reason than for forum functions and do not share or sell the information to any third party. I don't have any time to do any code changes or changes to the privacy policy today but will fix ASAP.