You did everything right. You studied, you took the test (maybe more than once), and you got the score your university asked for. Then the first lecture starts, and after ten minutes you realise you have understood about half of it. If that is how you feel right now, you are not alone, and your test result was not a mistake.
IELTS measured your English accurately. What it was never designed to measure is whether you can use that English in a British lecture theatre. Those are two different skills, and the gap between them catches out a lot of students in their first term.
Here is what changes when you leave the exam room.
Speed and accents. Exam recordings are clear and carefully paced. Your lecturer is not reading from a script. They speak at their normal speed, they go off on tangents (= start talking about something slightly different), and they may have a Glaswegian, Scouse or Nigerian accent that you have never heard on a practice test.
Listening and writing at the same time. In the test, you answer questions that someone else wrote. In a lecture, you decide for yourself what matters and write it down while the lecturer keeps talking.
The reading list. IELTS Reading gives you three texts and an hour. Your module may give you several chapters and articles a week, and nobody expects you to read every word of them. Knowing what to skip is a skill too, and hardly anyone teaches it.
So where do you start? Pick one thing to work on this week rather than everything at once.
For lectures, listen to the recording again if your university provides one, and this time listen for the signposts: ‘the main point here is’, ‘moving on to’, ‘to sum up’. Lecturers announce their structure out loud, and once you can hear it, the rest becomes much easier to follow. Outside lectures, choose a podcast or YouTube channel in your subject and listen at normal speed for fifteen minutes a day, with subtitles the first time and without them the second.
For reading, stop reading from the first word to the last. Read the abstract or introduction, then the conclusion, and only then decide whether the middle is worth your time. You are reading for your essay question, not for the sake of reading.
Your score got you in, which means your English is a real foundation to build on. What you need now is practice with the English of your own course, at real speed. That is exactly how my Academic English classes work: we use your own lecture recordings and reading lists instead of a coursebook. Book a free 30-minute chat and tell me what you are studying.