There is no official government medical cannabis card in the UK. Access starts...

https://www.herald-dispatch.com/sponsored/how-to-get-a-medical-cannabis-card-in-the-uk-step-by-step/article_a7f9fcb2-55db-40ff-857f-db6b98c92a97.html

There is no official government medical cannabis card in the UK. Access starts with a specialist consultation following a review of your medical records. If prescribed, you may choose to carry a private card as optional proof of your lawful medication.