You only need a student card if you are studying within the UK and need to access the buildings or Library. Otherwise you have full access to the online materials without a student card.
You will be contacted once your card is ready for collection but this will only be once you have completed online enrolment and uploaded a photo.
The email you receive will tell you when and where you will pick up your student card. You will need to have your photo ID with you in order to pick up your card.