To make a Tier 4 General Student application you must have 40 points under the UK Home Office points assessment. You can score
· 30 points for having a valid confirmation of acceptance for studies (CAS), issued by the University of St Andrews and for having acceptable English language skills; and
· 10 points for having enough money (also known as maintenance or funds) to cover your course fees and living costs.
You should not require your offer letter as part of the Tier 4 visa process.
Please see http://www.st-andrews.ac.uk/international/information/tier4students-oursharedresponsibilities/ for more information.