The TV licence is an annual fee of £174.50 for watching live TV or using BBC iPlayer. Most students do not need one.
If you live in university halls, your halls almost certainly has a licence that covers you. Check with your accommodation office. If you live in private accommodation and do not watch live TV or BBC iPlayer, you do not need one.
If you do not need a licence, declare this at tvlicensing.co.uk to stop receiving letters.
TV Licensing sends official-looking letters that can feel threatening. They are not fines — they are reminders. If you are exempt, simply declare online and the letters stop.