You will need to present evidence of the qualifications that the University used to assess your suitability for the course.
Your Confirmation of Acceptance of Studies (CAS) will tell you what the qualifications are. You must present certificates or official transcripts of the qualifications. From 5 November 2018, your documents may be copies; there will no longer be a requirement to submit original documents. Each document must clearly show: your name, the name of the academic institution, your programme title, the date of the award.
If you are applying in the UK, you must be able to prove that you have successfully completed your most recent course of study through official transcripts or a certificate showing that you have been awarded the qualification, or a letter from your institution stating that you have successfully completed your course of study.