Are you trying to make a CMS page where the additional attributes for some recipient are displayed?

(The §a§ etc placeholders should work normally when sending the CMS page as a mailing in EPiServer Mail.)

Something like this should be a starting point:

IRecipientSource theSource = EPiServerMailModule.GetRecipientSource(...);

Recipient recipient = theSource.GetRecipient(...);

And on the recipient object the property Attributes should have the relevant data.

However, GetRecipient takes the Guid that identifies the recipient, which you may or may not have handy in the codebehind of that CMS page.