If you sell goods – perhaps books or CDs, to Europe, you will need to have an EORI number (Economic Operator Registration and Identification) that begins with GB. In this video I share how you can get one. And here’s the link to the relevant page:
https://www.gov.uk/prepare-export-from-uk-after-brexit
Exporting goods to EU after 31/10/19 from Alison Moore on Vimeo.