There’s no official UK government cannabis card. Access is prescription-first...

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’s no official UK government cannabis card. Access is prescription-first via a specialist consultant after reviewing your medical records. If prescribed, you can opt for a private clinic card as optional proof of lawful use for police or employers.